Where discoveries are announced and described…
2015 |
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| 27. | Fukui, A., Gould, A., Sumi, T., Bennett, D. P., Bond, I. A., Han, C., Suzuki, D., Beaulieu, J.-P., Batista, V., Udalski, A., Street, R. A., Tsapras, Y., Hundertmark, M., Abe, F., Bhattacharya, A., Freeman, M., Itow, Y., Ling, C. H., Koshimoto, N., Masuda, K., Matsubara, Y., Muraki, Y., Ohnishi, K., Philpott, L. C., Rattenbury, N., Saito, T., Sullivan, D. J., Tristram, P. J., Yonehara, A., Choi, J.-Y., Christie, G. W., DePoy, D. L., Dong, Subo, Drummond, J., Gaudi, B. S., Hwang, K.-H., Kavka, A., Lee, C. U., McCormick, J., Natusch, T., Ngan, H., Park, H., Pogge, R. W., Shin, I.-G., Tan, T.-G., Yee, J. C., Szymański, M. K., Pietrzyński, G., Soszyński, I., Poleski, R., Kozłowski, S., Pietrukowicz, P., Ulaczyk, K., Bramich, Ł Wyrzykowski D. M., Browne, P., Dominik, M., Horne, K., Ipatov, S., Kains, N., Snodgrass, C., Steele, I. A. OGLE-2012-BLG-0563Lb: a Saturn-mass Planet around an M Dwarf with the Mass Constrained by Subaru AO imaging Journal Article The Astrophysical Journal, 809 (1), pp. 74, 2015, ISSN: 1538-4357, (arXiv: 1506.08850). @article{fukui_ogle-2012-blg-0563lb:_2015, title = {OGLE-2012-BLG-0563Lb: a Saturn-mass Planet around an M Dwarf with the Mass Constrained by Subaru AO imaging}, author = {Fukui, A. and Gould, A. and Sumi, T. and Bennett, D. P. and Bond, I. A. and Han, C. and Suzuki, D. and Beaulieu, J.-P. and Batista, V. and Udalski, A. and Street, R. A. and Tsapras, Y. and Hundertmark, M. and Abe, F. and Bhattacharya, A. and Freeman, M. and Itow, Y. and Ling, C. H. and Koshimoto, N. and Masuda, K. and Matsubara, Y. and Muraki, Y. and Ohnishi, K. and Philpott, L. C. and Rattenbury, N. and Saito, T. and Sullivan, D. J. and Tristram, P. J. and Yonehara, A. and Choi, J.-Y. and Christie, G. W. and DePoy, D. L. and Dong, Subo and Drummond, J. and Gaudi, B. S. and Hwang, K.-H. and Kavka, A. and Lee, C. U. and McCormick, J. and Natusch, T. and Ngan, H. and Park, H. and Pogge, R. W. and Shin, I.-G. and Tan, T.-G. and Yee, J. C. and Szymański, M. K. and Pietrzyński, G. and Soszyński, I. and Poleski, R. and Kozłowski, S. and Pietrukowicz, P. and Ulaczyk, K. and Bramich, Ł Wyrzykowski D. M. and Browne, P. and Dominik, M. and Horne, K. and Ipatov, S. and Kains, N. and Snodgrass, C. and Steele, I. A.}, url = {http://arxiv.org/abs/1506.08850}, doi = {10.1088/0004-637X/809/1/74}, issn = {1538-4357}, year = {2015}, date = {2015-08-01}, urldate = {2016-12-24}, journal = {The Astrophysical Journal}, volume = {809}, number = {1}, pages = {74}, abstract = {We report the discovery of a microlensing exoplanet OGLE-2012-BLG-0563Lb with the planet-star mass ratio textasciitilde1 x 10textasciicircum-3. Intensive photometric observations of a high-magnification microlensing event allow us to detect a clear signal of the planet. Although no parallax signal is detected in the light curve, we instead succeed at detecting the flux from the host star in high-resolution JHK'-band images obtained by the Subaru/AO188 and IRCS instruments, allowing us to constrain the absolute physical parameters of the planetary system. With the help of a spectroscopic information about the source star obtained during the high-magnification state by Bensby et al., we find that the lens system is located at 1.3textasciicircum+0.6_-0.8 kpc from us, and consists of an M dwarf (0.34textasciicircum+0.12_-0.20 M_sun) orbited by a Saturn-mass planet (0.39textasciicircum+0.14_-0.23 M_Jup) at the projected separation of 0.74textasciicircum+0.26_-0.42 AU (close model) or 4.3textasciicircum+1.5_-2.5 AU (wide model). The probability of contamination in the host star's flux, which would reduce the masses by a factor of up to three, is estimated to be 17%. This possibility can be tested by future high-resolution imaging. We also estimate the (J-Ks) and (H-Ks) colors of the host star, which are marginally consistent with a low metallicity mid-to-early M dwarf, although further observations are required for the metallicity to be conclusive. This is the fifth sub-Jupiter-mass (0.2textlessm_p/M_Juptextless1) microlensing planet around an M dwarf with the mass well constrained. The relatively rich harvest of sub-Jupiters around M dwarfs is contrasted with a possible paucity of textasciitilde1--2 Jupiter-mass planets around the same type of star, which can be explained by the planetary formation process in the core-accretion scheme.}, note = {arXiv: 1506.08850}, keywords = {}, pubstate = {published}, tppubtype = {article} } We report the discovery of a microlensing exoplanet OGLE-2012-BLG-0563Lb with the planet-star mass ratio textasciitilde1 x 10textasciicircum-3. Intensive photometric observations of a high-magnification microlensing event allow us to detect a clear signal of the planet. Although no parallax signal is detected in the light curve, we instead succeed at detecting the flux from the host star in high-resolution JHK'-band images obtained by the Subaru/AO188 and IRCS instruments, allowing us to constrain the absolute physical parameters of the planetary system. With the help of a spectroscopic information about the source star obtained during the high-magnification state by Bensby et al., we find that the lens system is located at 1.3textasciicircum+0.6_-0.8 kpc from us, and consists of an M dwarf (0.34textasciicircum+0.12_-0.20 M_sun) orbited by a Saturn-mass planet (0.39textasciicircum+0.14_-0.23 M_Jup) at the projected separation of 0.74textasciicircum+0.26_-0.42 AU (close model) or 4.3textasciicircum+1.5_-2.5 AU (wide model). The probability of contamination in the host star's flux, which would reduce the masses by a factor of up to three, is estimated to be 17%. This possibility can be tested by future high-resolution imaging. We also estimate the (J-Ks) and (H-Ks) colors of the host star, which are marginally consistent with a low metallicity mid-to-early M dwarf, although further observations are required for the metallicity to be conclusive. This is the fifth sub-Jupiter-mass (0.2textlessm_p/M_Juptextless1) microlensing planet around an M dwarf with the mass well constrained. The relatively rich harvest of sub-Jupiters around M dwarfs is contrasted with a possible paucity of textasciitilde1--2 Jupiter-mass planets around the same type of star, which can be explained by the planetary formation process in the core-accretion scheme. |
| 26. | Mancini, L., Hartman, J. D., Penev, K., Bakos, G. A., Brahm, R., Ciceri, S., Henning, Th, Csubry, Z., Bayliss, D., Zhou, G., Rabus, M., de Val-Borro, M., Espinoza, N., Jordan, A., Suc, V., Bhatti, W., Schmidt, B., Sato, B., Tan, T. G., Wright, D. J., Tinney, C. G., Addison, B. C., Noyes, R. W., Lazar, J., Papp, I., Sari, P. HATS-13b and HATS-14b: two transiting hot Jupiters from the HATSouth survey Journal Article Astronomy & Astrophysics, 580 , pp. A63, 2015, ISSN: 0004-6361, 1432-0746, (arXiv: 1503.03469). @article{mancini_hats-13b_2015, title = {HATS-13b and HATS-14b: two transiting hot Jupiters from the HATSouth survey}, author = {Mancini, L. and Hartman, J. D. and Penev, K. and Bakos, G. A. and Brahm, R. and Ciceri, S. and Henning, Th and Csubry, Z. and Bayliss, D. and Zhou, G. and Rabus, M. and de Val-Borro, M. and Espinoza, N. and Jordan, A. and Suc, V. and Bhatti, W. and Schmidt, B. and Sato, B. and Tan, T. G. and Wright, D. J. and Tinney, C. G. and Addison, B. C. and Noyes, R. W. and Lazar, J. and Papp, I. and Sari, P.}, url = {http://arxiv.org/abs/1503.03469}, doi = {10.1051/0004-6361/201526069}, issn = {0004-6361, 1432-0746}, year = {2015}, date = {2015-08-01}, urldate = {2016-12-24}, journal = {Astronomy & Astrophysics}, volume = {580}, pages = {A63}, abstract = {We report the discovery of HATS-13b and HATS-14b, two hot-Jupiter transiting planets discovered by the HATSouth survey. The host stars are quite similar to each other (HATS-13: V = 13.9 mag, M* = 0.96 Msun, R* = 0.89 Rsun}, note = {arXiv: 1503.03469}, keywords = {}, pubstate = {published}, tppubtype = {article} } We report the discovery of HATS-13b and HATS-14b, two hot-Jupiter transiting planets discovered by the HATSouth survey. The host stars are quite similar to each other (HATS-13: V = 13.9 mag, M* = 0.96 Msun, R* = 0.89 Rsun |
| 25. | Brahm, R., Jordán, A., Hartman, J. D., Bakos, G. Á, Bayliss, D., Penev, K., Zhou, G., Ciceri, S., Rabus, M., Espinoza, N., Mancini, L., de Val-Borro, M., Bhatti, W., Sato, B., Tan, T. G., Csubry, Z., Buchhave, L., Henning, T., Schmidt, B., Suc, V., Noyes, R. W., Papp, I., Lázár, J., Sári, P. HATS-9b and HATS-10b: Two Compact Hot Jupiters in Field 7 of the K2 Mission Journal Article The Astronomical Journal, 150 (1), pp. 33, 2015, ISSN: 1538-3881, (arXiv: 1503.00062). @article{brahm_hats-9b_2015, title = {HATS-9b and HATS-10b: Two Compact Hot Jupiters in Field 7 of the K2 Mission}, author = {Brahm, R. and Jordán, A. and Hartman, J. D. and Bakos, G. Á and Bayliss, D. and Penev, K. and Zhou, G. and Ciceri, S. and Rabus, M. and Espinoza, N. and Mancini, L. and de Val-Borro, M. and Bhatti, W. and Sato, B. and Tan, T. G. and Csubry, Z. and Buchhave, L. and Henning, T. and Schmidt, B. and Suc, V. and Noyes, R. W. and Papp, I. and Lázár, J. and Sári, P.}, url = {http://arxiv.org/abs/1503.00062}, doi = {10.1088/0004-6256/150/1/33}, issn = {1538-3881}, year = {2015}, date = {2015-07-01}, urldate = {2016-12-24}, journal = {The Astronomical Journal}, volume = {150}, number = {1}, pages = {33}, abstract = {We report the discovery of two transiting extrasolar planets by the HATSouth survey. HATS-9b orbits an old (10.8 $textbackslashpm$ 1.5 Gyr) V=13.3 G dwarf star, with a period P = 1.9153 d. The host star has a mass of 1.03 M$_textbackslashodot$, radius of 1.503 R$_textbackslashodot$ and effective temperature 5366 $textbackslashpm$ 70 K. The planetary companion has a mass of 0.837 M$_J$, and radius of 1.065 R$_J$ yielding a mean density of 0.85 g cm$textasciicircum-3$ . HATS-10b orbits a V=13.1 G dwarf star, with a period P = 3.3128 d. The host star has a mass of 1.1 M$_textbackslashodot$, radius of 1.11 R$_textbackslashodot$ and effective temperature 5880 $textbackslashpm$ 120 K. The planetary companion has a mass of 0.53 M$_J$, and radius of 0.97 R$_J$ yielding a mean density of 0.7 g cm$textasciicircum-3$ . Both planets are compact in comparison with planets receiving similar irradiation from their host stars, and lie in the nominal coordinates of Field 7 of K2 but only HATS-9b falls on working silicon. Future characterisation of HATS-9b with the exquisite photometric precision of the Kepler telescope may provide measurements of its reflected light signature.}, note = {arXiv: 1503.00062}, keywords = {}, pubstate = {published}, tppubtype = {article} } We report the discovery of two transiting extrasolar planets by the HATSouth survey. HATS-9b orbits an old (10.8 $textbackslashpm$ 1.5 Gyr) V=13.3 G dwarf star, with a period P = 1.9153 d. The host star has a mass of 1.03 M$_textbackslashodot$, radius of 1.503 R$_textbackslashodot$ and effective temperature 5366 $textbackslashpm$ 70 K. The planetary companion has a mass of 0.837 M$_J$, and radius of 1.065 R$_J$ yielding a mean density of 0.85 g cm$textasciicircum-3$ . HATS-10b orbits a V=13.1 G dwarf star, with a period P = 3.3128 d. The host star has a mass of 1.1 M$_textbackslashodot$, radius of 1.11 R$_textbackslashodot$ and effective temperature 5880 $textbackslashpm$ 120 K. The planetary companion has a mass of 0.53 M$_J$, and radius of 0.97 R$_J$ yielding a mean density of 0.7 g cm$textasciicircum-3$ . Both planets are compact in comparison with planets receiving similar irradiation from their host stars, and lie in the nominal coordinates of Field 7 of K2 but only HATS-9b falls on working silicon. Future characterisation of HATS-9b with the exquisite photometric precision of the Kepler telescope may provide measurements of its reflected light signature. |
| 24. | Reddy, Vishnu, Vokrouhlický, David, Bottke, William F., Pravec, Petr, Sanchez, Juan A., Gary, Bruce L., Klima, Rachel, Cloutis, Edward A., Galád, Adrián, Guan, Tan Thiam, Hornoch, Kamil, Izawa, Matthew R. M., Kušnirák, Peter, Corre, Lucille Le, Mann, Paul, Moskovitz, Nicholas, Skiff, Brian, Vraštil, Jan Link between the Potentially Hazardous Asteroid (86039) 1999 NC43 and the Chelyabinsk meteoroid tenuous Journal Article Icarus, 252 , pp. 129–143, 2015, ISSN: 00191035, (arXiv: 1502.05006). @article{reddy_link_2015, title = {Link between the Potentially Hazardous Asteroid (86039) 1999 NC43 and the Chelyabinsk meteoroid tenuous}, author = {Reddy, Vishnu and Vokrouhlický, David and Bottke, William F. and Pravec, Petr and Sanchez, Juan A. and Gary, Bruce L. and Klima, Rachel and Cloutis, Edward A. and Galád, Adrián and Guan, Tan Thiam and Hornoch, Kamil and Izawa, Matthew R. M. and Kušnirák, Peter and Corre, Lucille Le and Mann, Paul and Moskovitz, Nicholas and Skiff, Brian and Vraštil, Jan}, url = {http://arxiv.org/abs/1502.05006}, doi = {10.1016/j.icarus.2015.01.006}, issn = {00191035}, year = {2015}, date = {2015-05-01}, urldate = {2016-12-24}, journal = {Icarus}, volume = {252}, pages = {129--143}, abstract = {We explored the statistical and compositional link between Chelyabinsk meteoroid and potentially hazardous asteroid (86039) 1999 NC43 to investigate their proposed relation proposed by Borovitextbackslashčka et al. (2013). Using detailed computation we confirm that the orbit of the Chelyabinsk impactor is anomalously close to 1999 NC43. We find about (1-3) x 10-4 likelihood of that to happen by chance. Taking the standpoint that the Chelyabinsk impactor indeed separated from 1999 NC43 by a cratering or rotational fission event, we run a forward probability calculation, which is an independent statistical test. However, we find this scenario is unlikely at the about (10-3 -10-2) level. We also verified compositional link between Chelyabinska and 1999NC43. Mineralogical analysis of Chelyabinsk (LL chondrite) and (8) Flora (the largest member of the presumed LL chondrite parent family) shows that their olivine and pyroxene chemistries are similar to LL chondrites. Similar analysis of 1999 NC43 shows that its olivine and pyroxene chemistries are more similar to L chondrites than LL chondrites (like Chelyabinsk). We also took photometric observations of 1999 NC43 over 54 nights during two apparitions (2000, 2014). The lightcurve of 1999 NC43 resembles simulated lightcurves of tumblers in Short-Axis Mode with the mean wobbling angle 20-30 deg. While, a mechanism of the non-principal axis rotation excitation is unclear, we can rule out the formation of asteroid in disruption of its parent body as a plausible cause, as it is unlikely that the rotation of an asteroid fragment from catastrophic disruption would be nearly completely halted. Considering all these facts, we find the proposed link between the Chelyabinsk meteoroid and the asteroid 1999 NC43 to be unlikely.}, note = {arXiv: 1502.05006}, keywords = {}, pubstate = {published}, tppubtype = {article} } We explored the statistical and compositional link between Chelyabinsk meteoroid and potentially hazardous asteroid (86039) 1999 NC43 to investigate their proposed relation proposed by Borovitextbackslashčka et al. (2013). Using detailed computation we confirm that the orbit of the Chelyabinsk impactor is anomalously close to 1999 NC43. We find about (1-3) x 10-4 likelihood of that to happen by chance. Taking the standpoint that the Chelyabinsk impactor indeed separated from 1999 NC43 by a cratering or rotational fission event, we run a forward probability calculation, which is an independent statistical test. However, we find this scenario is unlikely at the about (10-3 -10-2) level. We also verified compositional link between Chelyabinska and 1999NC43. Mineralogical analysis of Chelyabinsk (LL chondrite) and (8) Flora (the largest member of the presumed LL chondrite parent family) shows that their olivine and pyroxene chemistries are similar to LL chondrites. Similar analysis of 1999 NC43 shows that its olivine and pyroxene chemistries are more similar to L chondrites than LL chondrites (like Chelyabinsk). We also took photometric observations of 1999 NC43 over 54 nights during two apparitions (2000, 2014). The lightcurve of 1999 NC43 resembles simulated lightcurves of tumblers in Short-Axis Mode with the mean wobbling angle 20-30 deg. While, a mechanism of the non-principal axis rotation excitation is unclear, we can rule out the formation of asteroid in disruption of its parent body as a plausible cause, as it is unlikely that the rotation of an asteroid fragment from catastrophic disruption would be nearly completely halted. Considering all these facts, we find the proposed link between the Chelyabinsk meteoroid and the asteroid 1999 NC43 to be unlikely. |
| 23. | Freeman, M., Philpott, L. C., Abe, F., Albrow, M. D., Bennett, D. P., Bond, I. A., Botzler, C. S., Bray, J. C., Cherrie, J. M., Christie, G. W., Dionnet, Z., Gould, A., Han, C., Heyrovsky, D., McCormick, J. M., Moorhouse, D. M., Muraki, Y., Natusch, T., Rattenbury, N. J., Skowron, J., Sumi, T., Suzuki, D., Tan, T.-G., Tristram, P. J., Yock, P. C. M. Can the masses of isolated planetary-mass gravitational lenses be measured by terrestrial parallax? Journal Article The Astrophysical Journal, 799 (2), pp. 181, 2015, ISSN: 1538-4357, (arXiv: 1412.1546). @article{freeman_can_2015, title = {Can the masses of isolated planetary-mass gravitational lenses be measured by terrestrial parallax?}, author = {Freeman, M. and Philpott, L. C. and Abe, F. and Albrow, M. D. and Bennett, D. P. and Bond, I. A. and Botzler, C. S. and Bray, J. C. and Cherrie, J. M. and Christie, G. W. and Dionnet, Z. and Gould, A. and Han, C. and Heyrovsky, D. and McCormick, J. M. and Moorhouse, D. M. and Muraki, Y. and Natusch, T. and Rattenbury, N. J. and Skowron, J. and Sumi, T. and Suzuki, D. and Tan, T.-G. and Tristram, P. J. and Yock, P. C. M.}, url = {http://arxiv.org/abs/1412.1546}, doi = {10.1088/0004-637X/799/2/181}, issn = {1538-4357}, year = {2015}, date = {2015-01-01}, urldate = {2016-12-24}, journal = {The Astrophysical Journal}, volume = {799}, number = {2}, pages = {181}, abstract = {Recently Sumi et al. (2011) reported evidence for a large population of planetary-mass objects (PMOs) that are either unbound or orbit host stars in orbits textgreater 10 AU. Their result was deduced from the statistical distribution of durations of gravitational microlensing events observed by the MOA collaboration during 2006 and 2007. Here we study the feasibility of measuring the mass of an individual PMO through microlensing by examining a particular event, MOA-2011-BLG-274. This event was unusual as the duration was short, the magnification high, the source-size effect large and the angular Einstein radius small. Also, it was intensively monitored from widely separated locations under clear skies at low air masses. Choi et al. (2012) concluded that the lens of the event may have been a PMO but they did not attempt a measurement of its mass. We report here a re-analysis of the event using re-reduced data. We confirm the results of Choi et al. and attempt a measurement of the mass and distance of the lens using the terrestrial parallax effect. Evidence for terrestrial parallax is found at a 3 sigma level of confidence. The best fit to the data yields the mass and distance of the lens as 0.80 +/- 0.30 M_J and 0.80 +/- 0.25 kpc respectively. We exclude a host star to the lens out to a separation textasciitilde 40 AU. Drawing on our analysis of MOA-2011-BLG-274 we propose observational strategies for future microlensing surveys to yield sharper results on PMOs including those down to super-Earth mass.}, note = {arXiv: 1412.1546}, keywords = {}, pubstate = {published}, tppubtype = {article} } Recently Sumi et al. (2011) reported evidence for a large population of planetary-mass objects (PMOs) that are either unbound or orbit host stars in orbits textgreater 10 AU. Their result was deduced from the statistical distribution of durations of gravitational microlensing events observed by the MOA collaboration during 2006 and 2007. Here we study the feasibility of measuring the mass of an individual PMO through microlensing by examining a particular event, MOA-2011-BLG-274. This event was unusual as the duration was short, the magnification high, the source-size effect large and the angular Einstein radius small. Also, it was intensively monitored from widely separated locations under clear skies at low air masses. Choi et al. (2012) concluded that the lens of the event may have been a PMO but they did not attempt a measurement of its mass. We report here a re-analysis of the event using re-reduced data. We confirm the results of Choi et al. and attempt a measurement of the mass and distance of the lens using the terrestrial parallax effect. Evidence for terrestrial parallax is found at a 3 sigma level of confidence. The best fit to the data yields the mass and distance of the lens as 0.80 +/- 0.30 M_J and 0.80 +/- 0.25 kpc respectively. We exclude a host star to the lens out to a separation textasciitilde 40 AU. Drawing on our analysis of MOA-2011-BLG-274 we propose observational strategies for future microlensing surveys to yield sharper results on PMOs including those down to super-Earth mass. |
| 22. | Hartman, J. D., Bayliss, D., Brahm, R., Bakos, G. Á, Mancini, L., Jordán, A., Penev, K., Rabus, M., Zhou, G., Butler, R. P., Espinoza, N., de Val-Borro, M., Bhatti, W., Csubry, Z., Ciceri, S., Henning, T., Schmidt, B., Arriagada, P., Shectman, S., Crane, J., Thompson, I., Suc, V., Csák, B., Tan, T. G., Noyes, R. W., Lázár, J., Papp, I., Sári, P. HATS-6b: A Warm Saturn Transiting an Early M Dwarf Star, and a Set of Empirical Relations for Characterizing K and M Dwarf Planet Hosts Journal Article The Astronomical Journal, 149 (5), pp. 166, 2015, ISSN: 1538-3881, (arXiv: 1408.1758). @article{hartman_hats-6b:_2015, title = {HATS-6b: A Warm Saturn Transiting an Early M Dwarf Star, and a Set of Empirical Relations for Characterizing K and M Dwarf Planet Hosts}, author = {Hartman, J. D. and Bayliss, D. and Brahm, R. and Bakos, G. Á and Mancini, L. and Jordán, A. and Penev, K. and Rabus, M. and Zhou, G. and Butler, R. P. and Espinoza, N. and de Val-Borro, M. and Bhatti, W. and Csubry, Z. and Ciceri, S. and Henning, T. and Schmidt, B. and Arriagada, P. and Shectman, S. and Crane, J. and Thompson, I. and Suc, V. and Csák, B. and Tan, T. G. and Noyes, R. W. and Lázár, J. and Papp, I. and Sári, P.}, url = {http://arxiv.org/abs/1408.1758}, doi = {10.1088/0004-6256/149/5/166}, issn = {1538-3881}, year = {2015}, date = {2015-01-01}, urldate = {2016-12-24}, journal = {The Astronomical Journal}, volume = {149}, number = {5}, pages = {166}, abstract = {We report the discovery by the HATSouth survey of HATS-6b, an extrasolar planet transiting a V=15.2 mag}, note = {arXiv: 1408.1758}, keywords = {}, pubstate = {published}, tppubtype = {article} } We report the discovery by the HATSouth survey of HATS-6b, an extrasolar planet transiting a V=15.2 mag |
2014 |
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| 21. | Martin, John C., Hambsch, Franz-Josef, Margutti, Raffaella, Tan, Thiam-Guan, Curtis, Ivan, Soderberg, Alicia A Closer Look at the Fluctuations in Brightness of SN 2009ip During Its Late 2012 Eruption Journal Article The Astronomical Journal, 149 (1), pp. 9, 2014, ISSN: 1538-3881, (arXiv: 1308.3682). @article{martin_closer_2014, title = {A Closer Look at the Fluctuations in Brightness of SN 2009ip During Its Late 2012 Eruption}, author = {Martin, John C. and Hambsch, Franz-Josef and Margutti, Raffaella and Tan, Thiam-Guan and Curtis, Ivan and Soderberg, Alicia}, url = {http://arxiv.org/abs/1308.3682}, doi = {10.1088/0004-6256/149/1/9}, issn = {1538-3881}, year = {2014}, date = {2014-12-01}, urldate = {2016-12-24}, journal = {The Astronomical Journal}, volume = {149}, number = {1}, pages = {9}, abstract = {The supernova impostor SN 2009ip has re-brightened several times since its initial discovery in August 2009. During its last outburst in late September 2012 it reached a peak brightness of m$_v$ $textbackslashsim$ 13.5 (M$_v$ brighter than -18) causing some to speculate that it had undergone a terminal core-collapse supernova. Relatively high-cadence multi-wavelength photometry of the post-peak decline revealed bumps in brightness infrequently observed in other Type IIn supernovae. These bumps occurred synchronously in all UV and optical bands with amplitudes of 0.1 -- 0.4 mag at intervals of 10 -- 30 days. Episodic continuum brightening and dimming in the UV and optical with these characteristics is not easilly explained within the context of models that have been proposed for the late September 2012 outburst of SN 2009ip. We also present evidence that the post peak fluctuations in brightness occur at regular intervals and raise more questions about their origin.}, note = {arXiv: 1308.3682}, keywords = {}, pubstate = {published}, tppubtype = {article} } The supernova impostor SN 2009ip has re-brightened several times since its initial discovery in August 2009. During its last outburst in late September 2012 it reached a peak brightness of m$_v$ $textbackslashsim$ 13.5 (M$_v$ brighter than -18) causing some to speculate that it had undergone a terminal core-collapse supernova. Relatively high-cadence multi-wavelength photometry of the post-peak decline revealed bumps in brightness infrequently observed in other Type IIn supernovae. These bumps occurred synchronously in all UV and optical bands with amplitudes of 0.1 -- 0.4 mag at intervals of 10 -- 30 days. Episodic continuum brightening and dimming in the UV and optical with these characteristics is not easilly explained within the context of models that have been proposed for the late September 2012 outburst of SN 2009ip. We also present evidence that the post peak fluctuations in brightness occur at regular intervals and raise more questions about their origin. |
| 20. | Henderson, C. B., Park, H., Sumi, T., Udalski, A., Gould, A., Tsapras, Y., Han, C., Gaudi, B. S., Bozza, V., Abe, F., Bennett, D. P., Bond, I. A., Botzler, C. S., Freeman, M., Fukui, A., Fukunaga, D., Itow, Y., Koshimoto, N., Ling, C. H., Masuda, K., Matsubara, Y., Muraki, Y., Namba, S., Ohnishi, K., Rattenbury, N. J., Saito, To, Sullivan, D. J., Suzuki, D., Sweatman, W. L., Tristram, P. J., Tsurumi, N., Wada, K., Yamai, N., Yock, P. C. M., Yonehara, A., Szymański, M. K., Kubiak, M., Pietrzyński, G., Soszyński, I., Skowron, J., Kozłowski, S., Poleski, R., Ulaczyk, K., Wyrzykowski, Ł, Pietrukowicz, P., Almeida, L. A., Bos, M., Choi, J.-Y., Christie, G. W., Depoy, D. L., Dong, Subo, Friedmann, M., Hwang, K.-H., Jablonski, F., Jung, Y. K., Kaspi, S., Lee, C.-U., Maoz, D., McCormick, J., Moorhouse, D., Natusch, T., Ngan, H., Pogge, R. W., Shin, I.-G., Shvartzvald, Y., Tan, T.-G., Thornley, G., Yee, J. C., Allan, A., Bramich, D. M., Browne, P., Dominik, M., Horne, K., Hundertmark, M., Jaimes, R. Figuera, Kains, N., Snodgrass, C., Steele, I. A., Street, R. A. Candidate Gravitational Microlensing Events for Future Direct Lens Imaging Journal Article The Astrophysical Journal, 794 (1), pp. 71, 2014, ISSN: 1538-4357, (arXiv: 1403.3092). @article{henderson_candidate_2014, title = {Candidate Gravitational Microlensing Events for Future Direct Lens Imaging}, author = {Henderson, C. B. and Park, H. and Sumi, T. and Udalski, A. and Gould, A. and Tsapras, Y. and Han, C. and Gaudi, B. S. and Bozza, V. and Abe, F. and Bennett, D. P. and Bond, I. A. and Botzler, C. S. and Freeman, M. and Fukui, A. and Fukunaga, D. and Itow, Y. and Koshimoto, N. and Ling, C. H. and Masuda, K. and Matsubara, Y. and Muraki, Y. and Namba, S. and Ohnishi, K. and Rattenbury, N. J. and Saito, To and Sullivan, D. J. and Suzuki, D. and Sweatman, W. L. and Tristram, P. J. and Tsurumi, N. and Wada, K. and Yamai, N. and Yock, P. C. M. and Yonehara, A. and Szymański, M. K. and Kubiak, M. and Pietrzyński, G. and Soszyński, I. and Skowron, J. and Kozłowski, S. and Poleski, R. and Ulaczyk, K. and Wyrzykowski, Ł and Pietrukowicz, P. and Almeida, L. A. and Bos, M. and Choi, J.-Y. and Christie, G. W. and Depoy, D. L. and Dong, Subo and Friedmann, M. and Hwang, K.-H. and Jablonski, F. and Jung, Y. K. and Kaspi, S. and Lee, C.-U. and Maoz, D. and McCormick, J. and Moorhouse, D. and Natusch, T. and Ngan, H. and Pogge, R. W. and Shin, I.-G. and Shvartzvald, Y. and Tan, T.-G. and Thornley, G. and Yee, J. C. and Allan, A. and Bramich, D. M. and Browne, P. and Dominik, M. and Horne, K. and Hundertmark, M. and Jaimes, R. Figuera and Kains, N. and Snodgrass, C. and Steele, I. A. and Street, R. A.}, url = {http://arxiv.org/abs/1403.3092}, doi = {10.1088/0004-637X/794/1/71}, issn = {1538-4357}, year = {2014}, date = {2014-09-01}, urldate = {2016-12-24}, journal = {The Astrophysical Journal}, volume = {794}, number = {1}, pages = {71}, abstract = {The mass of the lenses giving rise to Galactic microlensing events can be constrained by measuring the relative lens-source proper motion and lens flux. The flux of the lens can be separated from that of the source, companions to the source, and unrelated nearby stars with high-resolution images taken when the lens and source are spatially resolved. For typical ground-based adaptive optics (AO) or space-based observations, this requires either inordinately long time baselines or high relative proper motions. We provide a list of microlensing events toward the Galactic Bulge with high relative lens-source proper motion that are therefore good candidates for constraining the lens mass with future high-resolution imaging. We investigate all events from 2004 -- 2013 that display detectable finite-source effects, a feature that allows us to measure the proper motion. In total, we present 20 events with mu textgreatertextasciitilde 8 mas/yr. Of these, 14 were culled from previous analyses while 6 are new, including OGLE-2004-BLG-368, MOA-2005-BLG-36, OGLE-2012-BLG-0211, OGLE-2012-BLG-0456, MOA-2012-BLG-532, and MOA-2013-BLG-029. In textlesstextasciitilde12 years the lens and source of each event will be sufficiently separated for ground-based telescopes with AO systems or space telescopes to resolve each component and further characterize the lens system. Furthermore, for the most recent events, comparison of the lens flux estimates from images taken immediately to those estimated from images taken when the lens and source are resolved can be used to empirically check the robustness of the single-epoch method currently being used to estimate lens masses for many events.}, note = {arXiv: 1403.3092}, keywords = {}, pubstate = {published}, tppubtype = {article} } The mass of the lenses giving rise to Galactic microlensing events can be constrained by measuring the relative lens-source proper motion and lens flux. The flux of the lens can be separated from that of the source, companions to the source, and unrelated nearby stars with high-resolution images taken when the lens and source are spatially resolved. For typical ground-based adaptive optics (AO) or space-based observations, this requires either inordinately long time baselines or high relative proper motions. We provide a list of microlensing events toward the Galactic Bulge with high relative lens-source proper motion that are therefore good candidates for constraining the lens mass with future high-resolution imaging. We investigate all events from 2004 -- 2013 that display detectable finite-source effects, a feature that allows us to measure the proper motion. In total, we present 20 events with mu textgreatertextasciitilde 8 mas/yr. Of these, 14 were culled from previous analyses while 6 are new, including OGLE-2004-BLG-368, MOA-2005-BLG-36, OGLE-2012-BLG-0211, OGLE-2012-BLG-0456, MOA-2012-BLG-532, and MOA-2013-BLG-029. In textlesstextasciitilde12 years the lens and source of each event will be sufficiently separated for ground-based telescopes with AO systems or space telescopes to resolve each component and further characterize the lens system. Furthermore, for the most recent events, comparison of the lens flux estimates from images taken immediately to those estimated from images taken when the lens and source are resolved can be used to empirically check the robustness of the single-epoch method currently being used to estimate lens masses for many events. |
| 19. | Jordán, A., Brahm, R., Bakos, G. Á, Bayliss, D., Penev, K., Hartman, J. D., Zhou, G., Mancini, L., Mohler-Fischer, M., Ciceri, S., Sato, B., Csubry, Z., Rabus, M., Suc, V., Espinoza, N., Bhatti, W., de Val-Borro, M., Buchhave, L., Csák, B., Henning, T., Schmidt, B., Tan, T. G., Noyes, R. W., Béky, B., Butler, R. P., Shectman, S., Crane, J., Thompson, I., Williams, A., Martin, R., Contreras, C., Lázár, J., Papp, I., Sári, P. HATS-4b: A Dense Hot-Jupiter Transiting a Super Metal-Rich G Star Journal Article The Astronomical Journal, 148 (2), pp. 29, 2014, ISSN: 0004-6256, 1538-3881, (arXiv: 1402.6546). @article{jordan_hats-4b:_2014, title = {HATS-4b: A Dense Hot-Jupiter Transiting a Super Metal-Rich G Star}, author = {Jordán, A. and Brahm, R. and Bakos, G. Á and Bayliss, D. and Penev, K. and Hartman, J. D. and Zhou, G. and Mancini, L. and Mohler-Fischer, M. and Ciceri, S. and Sato, B. and Csubry, Z. and Rabus, M. and Suc, V. and Espinoza, N. and Bhatti, W. and de Val-Borro, M. and Buchhave, L. and Csák, B. and Henning, T. and Schmidt, B. and Tan, T. G. and Noyes, R. W. and Béky, B. and Butler, R. P. and Shectman, S. and Crane, J. and Thompson, I. and Williams, A. and Martin, R. and Contreras, C. and Lázár, J. and Papp, I. and Sári, P.}, url = {http://arxiv.org/abs/1402.6546}, doi = {10.1088/0004-6256/148/2/29}, issn = {0004-6256, 1538-3881}, year = {2014}, date = {2014-08-01}, urldate = {2016-12-24}, journal = {The Astronomical Journal}, volume = {148}, number = {2}, pages = {29}, abstract = {We report the discovery by the HATSouth survey of HATS-4b, an extrasolar planet transiting a V=13.46 mag G star. HATS-4b has a period of P = 2.5167 d, mass of Mp = 1.32 Mj, radius of Rp = 1.02 Rj and density of rho_p = 1.55 +- 0.16 g/cmtextasciicircum3 textasciitilde 1.24 rhoj. The host star has a mass of 1.00 Msun, a radius of 0.92 Rsun and a very high metallicity [Fe/H]= 0.43 +- 0.08. HATS-4b is among the densest known planets with masses between 1-2 Mj and is thus likely to have a significant content of heavy elements of the order of 75 Mearth. In this paper we present the data reduction, radial velocity measurement and stellar classification techniques adopted by the HATSouth survey for the CORALIE spectrograph. We also detail a technique to estimate simultaneously vsini and macroturbulence using high resolution spectra.}, note = {arXiv: 1402.6546}, keywords = {}, pubstate = {published}, tppubtype = {article} } We report the discovery by the HATSouth survey of HATS-4b, an extrasolar planet transiting a V=13.46 mag G star. HATS-4b has a period of P = 2.5167 d, mass of Mp = 1.32 Mj, radius of Rp = 1.02 Rj and density of rho_p = 1.55 +- 0.16 g/cmtextasciicircum3 textasciitilde 1.24 rhoj. The host star has a mass of 1.00 Msun, a radius of 0.92 Rsun and a very high metallicity [Fe/H]= 0.43 +- 0.08. HATS-4b is among the densest known planets with masses between 1-2 Mj and is thus likely to have a significant content of heavy elements of the order of 75 Mearth. In this paper we present the data reduction, radial velocity measurement and stellar classification techniques adopted by the HATSouth survey for the CORALIE spectrograph. We also detail a technique to estimate simultaneously vsini and macroturbulence using high resolution spectra. |
| 18. | Gould, A., Udalski, A., Shin, I.-G., Porritt, I., Skowron, J., Han, C., Yee, J. C., Kozłowski, S., Choi, J.-Y., Poleski, R., Wyrzykowski, Ł, Ulaczyk, K., Pietrukowicz, P., Mróz, P., Szymański, M. K., Kubiak, M., Soszyński, I., Pietrzyński, G., Gaudi, B. S., Christie, G. W., Drummond, J., McCormick, J., Natusch, T., Ngan, H., Tan, T.-G., Albrow, M., DePoy, D. L., Hwang, K.-H., Jung, Y. K., Lee, C.-U., Park, H., Pogge, R. W., Abe, F., Bennett, D. P., Bond, I. A., Botzler, C. S., Freeman, M., Fukui, A., Fukunaga, D., Itow, Y., Koshimoto, N., Larsen, P., Ling, C. H., Masuda, K., Matsubara, Y., Muraki, Y., Namba, S., Ohnishi, K., Philpott, L., Rattenbury, N. J., Saito, To, Sullivan, D. J., Sumi, T., Suzuki, D., Tristram, P. J., Tsurumi, N., Wada, K., Yamai, N., Yock, P. C. M., Yonehara, A., Shvartzvald, Y., Maoz, D., Kaspi, S., Friedmann, M. A Terrestrial Planet in a textasciitilde1 AU Orbit Around One Member of a textasciitilde15 AU Binary Journal Article Science, 345 (6192), pp. 46–49, 2014, ISSN: 0036-8075, 1095-9203, (arXiv: 1407.1115). @article{gould_terrestrial_2014, title = {A Terrestrial Planet in a textasciitilde1 AU Orbit Around One Member of a textasciitilde15 AU Binary}, author = {Gould, A. and Udalski, A. and Shin, I.-G. and Porritt, I. and Skowron, J. and Han, C. and Yee, J. C. and Kozłowski, S. and Choi, J.-Y. and Poleski, R. and Wyrzykowski, Ł and Ulaczyk, K. and Pietrukowicz, P. and Mróz, P. and Szymański, M. K. and Kubiak, M. and Soszyński, I. and Pietrzyński, G. and Gaudi, B. S. and Christie, G. W. and Drummond, J. and McCormick, J. and Natusch, T. and Ngan, H. and Tan, T.-G. and Albrow, M. and DePoy, D. L. and Hwang, K.-H. and Jung, Y. K. and Lee, C.-U. and Park, H. and Pogge, R. W. and Abe, F. and Bennett, D. P. and Bond, I. A. and Botzler, C. S. and Freeman, M. and Fukui, A. and Fukunaga, D. and Itow, Y. and Koshimoto, N. and Larsen, P. and Ling, C. H. and Masuda, K. and Matsubara, Y. and Muraki, Y. and Namba, S. and Ohnishi, K. and Philpott, L. and Rattenbury, N. J. and Saito, To and Sullivan, D. J. and Sumi, T. and Suzuki, D. and Tristram, P. J. and Tsurumi, N. and Wada, K. and Yamai, N. and Yock, P. C. M. and Yonehara, A. and Shvartzvald, Y. and Maoz, D. and Kaspi, S. and Friedmann, M.}, url = {http://arxiv.org/abs/1407.1115}, doi = {10.1126/science.1251527}, issn = {0036-8075, 1095-9203}, year = {2014}, date = {2014-07-01}, urldate = {2016-12-24}, journal = {Science}, volume = {345}, number = {6192}, pages = {46--49}, abstract = {We detect a cold, terrestrial planet in a binary-star system using gravitational microlensing. The planet has low mass (2 Earth masses) and lies projected at $a_textbackslashperp,ph$ textasciitilde 0.8 astronomical units (AU) from its host star, similar to the Earth-Sun distance. However, the planet temperature is much lower, Ttextless60 Kelvin, because the host star is only 0.10--0.15 solar masses and therefore more than 400 times less luminous than the Sun. The host is itself orbiting a slightly more massive companion with projected separation $a_textbackslashperp,ch=$10--15 AU. Straightforward modification of current microlensing search strategies could increase their sensitivity to planets in binary systems. With more detections, such binary-star/planetary systems could place constraints on models of planet formation and evolution. This detection is consistent with such systems being very common.}, note = {arXiv: 1407.1115}, keywords = {}, pubstate = {published}, tppubtype = {article} } We detect a cold, terrestrial planet in a binary-star system using gravitational microlensing. The planet has low mass (2 Earth masses) and lies projected at $a_textbackslashperp,ph$ textasciitilde 0.8 astronomical units (AU) from its host star, similar to the Earth-Sun distance. However, the planet temperature is much lower, Ttextless60 Kelvin, because the host star is only 0.10--0.15 solar masses and therefore more than 400 times less luminous than the Sun. The host is itself orbiting a slightly more massive companion with projected separation $a_textbackslashperp,ch=$10--15 AU. Straightforward modification of current microlensing search strategies could increase their sensitivity to planets in binary systems. With more detections, such binary-star/planetary systems could place constraints on models of planet formation and evolution. This detection is consistent with such systems being very common. |
| 17. | Yee, J. C., Han, C., Gould, A., Skowron, J., Bond, I. A., Udalski, A., Hundertmark, M., Monard, L. A. G., Porritt, I., Nelson, P., Bozza, V., Albrow, M. D., Choi, J.-Y., Christie, G. W., DePoy, D. L., Gaudi, B. S., Hwang, K.-H., Jung, Y. K., Lee, C.-U., McCormick, J., Natusch, T., Ngan, H., Park, H., Pogge, R. W., Shin, I.-G., Tan, T.-G., Abe, F., Bennett, D. P., Botzler, C. S., Freeman, M., Fukui, A., Fukunaga, D., Itow, Y., Koshimoto, N., Larsen, P., Ling, C. H., Masuda, K., Matsubara, Y., Muraki, Y., Namba, S., Ohnishi, K., Philpott, L., Rattenbury, N. J., Saito, To, Sullivan, D. J., Sumi, T., Sweatman, W. L., Suzuki, D., Tristram, P. J., Tsurumi, N., Wada, K., Yamai, N., Yock, P. C. M., Yonehara, A., Szymański, M. K., Ulaczyk, K., Kozłowski, S., Poleski, R., Wyrzykowski, Ł, Kubiak, M., Pietrukowicz, P., Pietrzyński, G., Soszyński, I., Bramich, D. M., Browne, P., Jaimes, R. Figuera, Horne, K., Ipatov, S., Kains, N., Snodgrass, C., Steele, I. A., Street, R., Tsapras, Y. MOA-2013-BLG-220Lb: Massive Planetary Companion to Galactic-Disk Host Journal Article The Astrophysical Journal, 790 (1), pp. 14, 2014, ISSN: 0004-637X, 1538-4357, (arXiv: 1403.2134). @article{yee_moa-2013-blg-220lb:_2014, title = {MOA-2013-BLG-220Lb: Massive Planetary Companion to Galactic-Disk Host}, author = {Yee, J. C. and Han, C. and Gould, A. and Skowron, J. and Bond, I. A. and Udalski, A. and Hundertmark, M. and Monard, L. A. G. and Porritt, I. and Nelson, P. and Bozza, V. and Albrow, M. D. and Choi, J.-Y. and Christie, G. W. and DePoy, D. L. and Gaudi, B. S. and Hwang, K.-H. and Jung, Y. K. and Lee, C.-U. and McCormick, J. and Natusch, T. and Ngan, H. and Park, H. and Pogge, R. W. and Shin, I.-G. and Tan, T.-G. and Abe, F. and Bennett, D. P. and Botzler, C. S. and Freeman, M. and Fukui, A. and Fukunaga, D. and Itow, Y. and Koshimoto, N. and Larsen, P. and Ling, C. H. and Masuda, K. and Matsubara, Y. and Muraki, Y. and Namba, S. and Ohnishi, K. and Philpott, L. and Rattenbury, N. J. and Saito, To and Sullivan, D. J. and Sumi, T. and Sweatman, W. L. and Suzuki, D. and Tristram, P. J. and Tsurumi, N. and Wada, K. and Yamai, N. and Yock, P. C. M. and Yonehara, A. and Szymański, M. K. and Ulaczyk, K. and Kozłowski, S. and Poleski, R. and Wyrzykowski, Ł and Kubiak, M. and Pietrukowicz, P. and Pietrzyński, G. and Soszyński, I. and Bramich, D. M. and Browne, P. and Jaimes, R. Figuera and Horne, K. and Ipatov, S. and Kains, N. and Snodgrass, C. and Steele, I. A. and Street, R. and Tsapras, Y.}, url = {http://arxiv.org/abs/1403.2134}, doi = {10.1088/0004-637X/790/1/14}, issn = {0004-637X, 1538-4357}, year = {2014}, date = {2014-07-01}, urldate = {2016-12-24}, journal = {The Astrophysical Journal}, volume = {790}, number = {1}, pages = {14}, abstract = {We report the discovery of MOA-2013-BLG-220Lb, which has a super-Jupiter mass ratio $q=3.01textbackslashpm 0.02textbackslashtimes 10textasciicircum-3$ relative to its host. The proper motion, $textbackslashmu=12.5textbackslashpm 1textbackslash, textbackslashrm mastextbackslash,textbackslashrm yrtextasciicircum-1$, is one of the highest for microlensing planets yet discovered, implying that it will be possible to separately resolve the host within $textbackslashsim 7$ years. Two separate lines of evidence imply that the planet and host are in the Galactic disk. The planet could have been detected and characterized purely with follow-up data, which has important implications for microlensing surveys, both current and into the LSST era.}, note = {arXiv: 1403.2134}, keywords = {}, pubstate = {published}, tppubtype = {article} } We report the discovery of MOA-2013-BLG-220Lb, which has a super-Jupiter mass ratio $q=3.01textbackslashpm 0.02textbackslashtimes 10textasciicircum-3$ relative to its host. The proper motion, $textbackslashmu=12.5textbackslashpm 1textbackslash, textbackslashrm mastextbackslash,textbackslashrm yrtextasciicircum-1$, is one of the highest for microlensing planets yet discovered, implying that it will be possible to separately resolve the host within $textbackslashsim 7$ years. Two separate lines of evidence imply that the planet and host are in the Galactic disk. The planet could have been detected and characterized purely with follow-up data, which has important implications for microlensing surveys, both current and into the LSST era. |
| 16. | Zhou, G., Bayliss, D., Hartman, J. D., Bakos, G. Á, Penev, K., Csubry, Z., Tan, T. G., Jordán, A., Mancini, L., Rabus, M., Brahm, R., Espinoza, N., Mohler-Fischer, M., Ciceri, S., Suc, V., Csák, B., Henning, T., Schmidt, B. The Mass-Radius Relationship for Very Low Mass Stars: Four New Discoveries from the HATSouth Survey Journal Article Monthly Notices of the Royal Astronomical Society, 437 (3), pp. 2831–2844, 2014, ISSN: 0035-8711, 1365-2966, (arXiv: 1310.7591). @article{zhou_mass-radius_2014, title = {The Mass-Radius Relationship for Very Low Mass Stars: Four New Discoveries from the HATSouth Survey}, author = {Zhou, G. and Bayliss, D. and Hartman, J. D. and Bakos, G. Á and Penev, K. and Csubry, Z. and Tan, T. G. and Jordán, A. and Mancini, L. and Rabus, M. and Brahm, R. and Espinoza, N. and Mohler-Fischer, M. and Ciceri, S. and Suc, V. and Csák, B. and Henning, T. and Schmidt, B.}, url = {http://arxiv.org/abs/1310.7591}, doi = {10.1093/mnras/stt2100}, issn = {0035-8711, 1365-2966}, year = {2014}, date = {2014-01-01}, urldate = {2016-12-24}, journal = {Monthly Notices of the Royal Astronomical Society}, volume = {437}, number = {3}, pages = {2831--2844}, abstract = {We report the discovery of four transiting F-M binary systems with companions between 0.1-0.2 Msun in mass by the HATSouth survey. These systems have been characterised via a global analysis of the HATSouth discovery data, combined with high-resolution radial velocities and accurate transit photometry observations. We determined the masses and radii of the component stars using a combination of two methods: isochrone fitting of spectroscopic primary star parameters, and equating spectroscopic primary star rotation velocity with spin-orbit synchronisation. These new very low mass companions are HATS550-016B (0.110 -0.006/+0.005 Msun, 0.147 -0.004/+0.003 Rsun), HATS551-019B (0.17 -0.01/+0.01 Msun, 0.18 -0.01/+0.01 Rsun), HATS551-021B (0.132 -0.005/+0.014 Msun, 0.154 -0.008/+0.006 Rsun), HATS553-001B (0.20 -0.02/+0.01 Msun, 0.22 -0.01/+0.01 Rsun). We examine our sample in the context of the radius anomaly for fully-convective low mass stars. Combining our sample with the 13 other well-studied very low mass stars, we find a tentative 5% systematic deviation between the measured radii and theoretical isochrone models.}, note = {arXiv: 1310.7591}, keywords = {}, pubstate = {published}, tppubtype = {article} } We report the discovery of four transiting F-M binary systems with companions between 0.1-0.2 Msun in mass by the HATSouth survey. These systems have been characterised via a global analysis of the HATSouth discovery data, combined with high-resolution radial velocities and accurate transit photometry observations. We determined the masses and radii of the component stars using a combination of two methods: isochrone fitting of spectroscopic primary star parameters, and equating spectroscopic primary star rotation velocity with spin-orbit synchronisation. These new very low mass companions are HATS550-016B (0.110 -0.006/+0.005 Msun, 0.147 -0.004/+0.003 Rsun), HATS551-019B (0.17 -0.01/+0.01 Msun, 0.18 -0.01/+0.01 Rsun), HATS551-021B (0.132 -0.005/+0.014 Msun, 0.154 -0.008/+0.006 Rsun), HATS553-001B (0.20 -0.02/+0.01 Msun, 0.22 -0.01/+0.01 Rsun). We examine our sample in the context of the radius anomaly for fully-convective low mass stars. Combining our sample with the 13 other well-studied very low mass stars, we find a tentative 5% systematic deviation between the measured radii and theoretical isochrone models. |
| 15. | Tsapras, Y., Choi, J.-Y., Street, R. A., Han, C., Bozza, V., Gould, A., Dominik, M., Beaulieu, J.-P., Udalski, A., Jørgensen, U. G., Sumi, T., Bramich, D. M., Browne, P., Horne, K., Hundertmark, M., Ipatov, S., Kains, N., Snodgrass, C., Steele, I. A., Alsubai, K. A., Andersen, J. M., Novati, S. Calchi, Damerdji, Y., Diehl, C., Elyiv, A., Giannini, E., Hardis, S., Harpsøe, K., Hinse, T. C., Juncher, D., Kerins, E., Korhonen, H., Liebig, C., Mancini, L., Mathiasen, M., Penny, M. T., Rabus, M., Rahvar, S., Scarpetta, G., Skottfelt, J., Southworth, J., Surdej, J., Tregloan-Reed, J., Vilela, C., Wambsganss, J., Skowron, J., Poleski, R., Kozłowski, S., Wyrzykowski, Łukasz, Szymański, M. K., Kubiak, M., Pietrukowicz, P., Pietrzyński, G., Soszyński, I., Ulaczyk, K., Albrow, M. D., Bachelet, E., Barry, R., Batista, V., Bhattacharya, A., Brillant, S., Caldwell, J. A. R., Cassan, A., Cole, A., Corrales, E., Coutures, Ch, Dieters, S., Prester, D. Dominis, Donatowicz, J., Fouqué, P., Greenhill, J., Kane, S. R., Kubas, D., Marquette, J.-B., Menzies, J., P`ere, C., Pollard, K. R., Wouters, D., Christie, G., DePoy, D. L., Dong, S., Drummond, J., Gaudi, B. S., Henderson, C. B., Hwang, K. H., Jung, Y. K., Kavka, A., Koo, J.-R., Lee, C.-U., Maoz, D., Monard, L. A. G., Natusch, T., Ngan, H., Park, H., Pogge, R. W., Porritt, I., Shin, I.-G., Shvartzvald, Y., Tan, T. G., Yee, J. C., Abe, F., Bennett, D. P., Bond, I. A., Botzler, C. S., Freeman, M., Fukui, A., Fukunaga, D., Itow, Y., Koshimoto, N., Ling, C. H., Masuda, K., Matsubara, Y., Muraki, Y., Namba, S., Ohnishi, K., Rattenbury, N. J., Saito, To, Sullivan, D. J., Sweatman, W. L., Suzuki, D., Tristram, P. J., Tsurumi, N., Wada, K., Yamai, N., Yonehara, P. C. M. Yock A. A Super-Jupiter orbiting a late-type star: A refined analysis of microlensing event OGLE-2012-BLG-0406 Journal Article The Astrophysical Journal, 782 (1), pp. 48, 2014, ISSN: 0004-637X, 1538-4357, (arXiv: 1310.2428). @article{tsapras_super-jupiter_2014, title = {A Super-Jupiter orbiting a late-type star: A refined analysis of microlensing event OGLE-2012-BLG-0406}, author = {Tsapras, Y. and Choi, J.-Y. and Street, R. A. and Han, C. and Bozza, V. and Gould, A. and Dominik, M. and Beaulieu, J.-P. and Udalski, A. and Jørgensen, U. G. and Sumi, T. and Bramich, D. M. and Browne, P. and Horne, K. and Hundertmark, M. and Ipatov, S. and Kains, N. and Snodgrass, C. and Steele, I. A. and Alsubai, K. A. and Andersen, J. M. and Novati, S. Calchi and Damerdji, Y. and Diehl, C. and Elyiv, A. and Giannini, E. and Hardis, S. and Harpsøe, K. and Hinse, T. C. and Juncher, D. and Kerins, E. and Korhonen, H. and Liebig, C. and Mancini, L. and Mathiasen, M. and Penny, M. T. and Rabus, M. and Rahvar, S. and Scarpetta, G. and Skottfelt, J. and Southworth, J. and Surdej, J. and Tregloan-Reed, J. and Vilela, C. and Wambsganss, J. and Skowron, J. and Poleski, R. and Kozłowski, S. and Wyrzykowski, Łukasz and Szymański, M. K. and Kubiak, M. and Pietrukowicz, P. and Pietrzyński, G. and Soszyński, I. and Ulaczyk, K. and Albrow, M. D. and Bachelet, E. and Barry, R. and Batista, V. and Bhattacharya, A. and Brillant, S. and Caldwell, J. A. R. and Cassan, A. and Cole, A. and Corrales, E. and Coutures, Ch and Dieters, S. and Prester, D. Dominis and Donatowicz, J. and Fouqué, P. and Greenhill, J. and Kane, S. R. and Kubas, D. and Marquette, J.-B. and Menzies, J. and P`ere, C. and Pollard, K. R. and Wouters, D. and Christie, G. and DePoy, D. L. and Dong, S. and Drummond, J. and Gaudi, B. S. and Henderson, C. B. and Hwang, K. H. and Jung, Y. K. and Kavka, A. and Koo, J.-R. and Lee, C.-U. and Maoz, D. and Monard, L. A. G. and Natusch, T. and Ngan, H. and Park, H. and Pogge, R. W. and Porritt, I. and Shin, I.-G. and Shvartzvald, Y. and Tan, T. G. and Yee, J. C. and Abe, F. and Bennett, D. P. and Bond, I. A. and Botzler, C. S. and Freeman, M. and Fukui, A. and Fukunaga, D. and Itow, Y. and Koshimoto, N. and Ling, C. H. and Masuda, K. and Matsubara, Y. and Muraki, Y. and Namba, S. and Ohnishi, K. and Rattenbury, N. J. and Saito, To and Sullivan, D. J. and Sweatman, W. L. and Suzuki, D. and Tristram, P. J. and Tsurumi, N. and Wada, K. and Yamai, N. and Yonehara, P. C. M. Yock A.}, url = {http://arxiv.org/abs/1310.2428}, doi = {10.1088/0004-637X/782/1/48}, issn = {0004-637X, 1538-4357}, year = {2014}, date = {2014-01-01}, urldate = {2016-12-24}, journal = {The Astrophysical Journal}, volume = {782}, number = {1}, pages = {48}, abstract = {We present a detailed analysis of survey and follow-up observations of microlensing event OGLE-2012-BLG-0406 based on data obtained from 10 different observatories. Intensive coverage of the lightcurve, especially the perturbation part, allowed us to accurately measure the parallax effect and lens orbital motion. Combining our measurement of the lens parallax with the angular Einstein radius determined from finite-source effects, we estimate the physical parameters of the lens system. We find that the event was caused by a $2.73textbackslashpm 0.43textbackslash M_textbackslashrm J$ planet orbiting a $0.44textbackslashpm 0.07textbackslash M_textbackslashodot$ early M-type star. The distance to the lens is $4.97textbackslashpm 0.29$textbackslash kpc and the projected separation between the host star and its planet at the time of the event is $3.45textbackslashpm 0.26$ AU. We find that the additional coverage provided by follow-up observations, especially during the planetary perturbation, leads to a more accurate determination of the physical parameters of the lens.}, note = {arXiv: 1310.2428}, keywords = {}, pubstate = {published}, tppubtype = {article} } We present a detailed analysis of survey and follow-up observations of microlensing event OGLE-2012-BLG-0406 based on data obtained from 10 different observatories. Intensive coverage of the lightcurve, especially the perturbation part, allowed us to accurately measure the parallax effect and lens orbital motion. Combining our measurement of the lens parallax with the angular Einstein radius determined from finite-source effects, we estimate the physical parameters of the lens system. We find that the event was caused by a $2.73textbackslashpm 0.43textbackslash M_textbackslashrm J$ planet orbiting a $0.44textbackslashpm 0.07textbackslash M_textbackslashodot$ early M-type star. The distance to the lens is $4.97textbackslashpm 0.29$textbackslash kpc and the projected separation between the host star and its planet at the time of the event is $3.45textbackslashpm 0.26$ AU. We find that the additional coverage provided by follow-up observations, especially during the planetary perturbation, leads to a more accurate determination of the physical parameters of the lens. |
2013 |
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| 14. | Han, C., Jung, Y. K., Udalski, A., Sumi, T., Gaudi, B. S., Gould, A., Bennett, D. P., Tsapras, Y., Szymański, M. K., Kubiak, M., Pietrzyński, G., Soszyński, I., Skowron, J., Kozłowski, S., Poleski, R., Ulaczyk, K., Wyrzykowski, Ł, Pietrukowicz, P., Abe, F., Bond, I. A., Botzler, C. S., Chote, P., Freeman, M., Fukui, A., Furusawa, K., Harris, P., Itow, Y., Ling, C. H., Masuda, K., Matsubara, Y., Muraki, Y., Ohnishi, K., Rattenbury, N. J., Saito, To, Sullivan, D. J., Sweatman, W. L., Suzuki, D., Tristram, P. J., Wada, K., Yock, P. C. M., Batista, V., Christie, G., Choi, J.-Y., DePoy, D. L., Dong, Subo, Hwang, K.-H., Kavka, A., Lee, C.-U., Monard, L. A. G., Natusch, T., Ngan, H., Park, H., Pogge, R. W., Porritt, I., Shin, I.-G., Tan, T. G., Yee, J. C., Alsubai, K. A., Bozza, V., Bramich, D. M., Browne, P., Dominik, M., Horne, K., Hundertmark, M., Ipatov, S., Kains, N., Liebig, C., Snodgrass, C., Steele, I. A., Street, R. A. Microlensing Discovery of a Tight, Low Mass-ratio Planetary-mass Object around an Old, Field Brown Dwarf Journal Article The Astrophysical Journal, 778 (1), pp. 38, 2013, ISSN: 0004-637X, 1538-4357, (arXiv: 1307.6335). @article{han_microlensing_2013, title = {Microlensing Discovery of a Tight, Low Mass-ratio Planetary-mass Object around an Old, Field Brown Dwarf}, author = {Han, C. and Jung, Y. K. and Udalski, A. and Sumi, T. and Gaudi, B. S. and Gould, A. and Bennett, D. P. and Tsapras, Y. and Szymański, M. K. and Kubiak, M. and Pietrzyński, G. and Soszyński, I. and Skowron, J. and Kozłowski, S. and Poleski, R. and Ulaczyk, K. and Wyrzykowski, Ł and Pietrukowicz, P. and Abe, F. and Bond, I. A. and Botzler, C. S. and Chote, P. and Freeman, M. and Fukui, A. and Furusawa, K. and Harris, P. and Itow, Y. and Ling, C. H. and Masuda, K. and Matsubara, Y. and Muraki, Y. and Ohnishi, K. and Rattenbury, N. J. and Saito, To and Sullivan, D. J. and Sweatman, W. L. and Suzuki, D. and Tristram, P. J. and Wada, K. and Yock, P. C. M. and Batista, V. and Christie, G. and Choi, J.-Y. and DePoy, D. L. and Dong, Subo and Hwang, K.-H. and Kavka, A. and Lee, C.-U. and Monard, L. A. G. and Natusch, T. and Ngan, H. and Park, H. and Pogge, R. W. and Porritt, I. and Shin, I.-G. and Tan, T. G. and Yee, J. C. and Alsubai, K. A. and Bozza, V. and Bramich, D. M. and Browne, P. and Dominik, M. and Horne, K. and Hundertmark, M. and Ipatov, S. and Kains, N. and Liebig, C. and Snodgrass, C. and Steele, I. A. and Street, R. A.}, url = {http://arxiv.org/abs/1307.6335}, doi = {10.1088/0004-637X/778/1/38}, issn = {0004-637X, 1538-4357}, year = {2013}, date = {2013-11-01}, urldate = {2016-12-24}, journal = {The Astrophysical Journal}, volume = {778}, number = {1}, pages = {38}, abstract = {Observations of accretion disks around young brown dwarfs have led to the speculation that they may form planetary systems similar to normal stars. While there have been several detections of planetary-mass objects around brown dwarfs (2MASS 1207-3932 and 2MASS 0441-2301), these companions have relatively large mass ratios and projected separations, suggesting that they formed in a manner analogous to stellar binaries. We present the discovery of a planetary-mass object orbiting a field brown dwarf via gravitational microlensing, OGLE-2012-BLG-0358Lb. The system is a low secondary/primary mass ratio (0.080 +- 0.001), relatively tightly-separated (textasciitilde0.87 AU) binary composed of a planetary-mass object with 1.9 +- 0.2 Jupiter masses orbiting a brown dwarf with a mass 0.022 M_Sun. The relatively small mass ratio and separation suggest that the companion may have formed in a protoplanetary disk around the brown dwarf host, in a manner analogous to planets.}, note = {arXiv: 1307.6335}, keywords = {}, pubstate = {published}, tppubtype = {article} } Observations of accretion disks around young brown dwarfs have led to the speculation that they may form planetary systems similar to normal stars. While there have been several detections of planetary-mass objects around brown dwarfs (2MASS 1207-3932 and 2MASS 0441-2301), these companions have relatively large mass ratios and projected separations, suggesting that they formed in a manner analogous to stellar binaries. We present the discovery of a planetary-mass object orbiting a field brown dwarf via gravitational microlensing, OGLE-2012-BLG-0358Lb. The system is a low secondary/primary mass ratio (0.080 +- 0.001), relatively tightly-separated (textasciitilde0.87 AU) binary composed of a planetary-mass object with 1.9 +- 0.2 Jupiter masses orbiting a brown dwarf with a mass 0.022 M_Sun. The relatively small mass ratio and separation suggest that the companion may have formed in a protoplanetary disk around the brown dwarf host, in a manner analogous to planets. |
| 13. | Mancini, L., Ciceri, S., Chen, G., Tregloan-Reed, J., Fortney, J. J., Southworth, J., Tan, T. G., Burgdorf, M., Novati, S. Calchi, Dominik, M., Fang, X.-S., Finet, F., Gerner, T., Hardis, S., Hinse, T. C., Jorgensen, U. G., Liebig, C., Nikolov, N., Ricci, D., Schaefer, S., Schoenebeck, F., Skottfelt, J., Wertz, O., Alsubai, K. A., Bozza, V., Browne, P., Dodds, P., Gu, S.-H., Harpsoe, K., Henning, Th, Hundertmark, M., Jessen-Hansen, J., Kains, N., Kerins, E., Kjeldsen, H., Lund, M. N., Lundkvist, M., Madhusudhan, N., Mathiasen, M., Penny, M. T., Proft, S., Rahvar, S., Sahu, K., Scarpetta, G., Snodgrass, C., Surdej, J. Physical properties, transmission and emission spectra of the WASP-19 planetary system from multi-colour photometry Journal Article Monthly Notices of the Royal Astronomical Society, 436 (1), pp. 2–18, 2013, ISSN: 0035-8711, 1365-2966, (arXiv: 1306.6384). @article{mancini_physical_2013, title = {Physical properties, transmission and emission spectra of the WASP-19 planetary system from multi-colour photometry}, author = {Mancini, L. and Ciceri, S. and Chen, G. and Tregloan-Reed, J. and Fortney, J. J. and Southworth, J. and Tan, T. G. and Burgdorf, M. and Novati, S. Calchi and Dominik, M. and Fang, X.-S. and Finet, F. and Gerner, T. and Hardis, S. and Hinse, T. C. and Jorgensen, U. G. and Liebig, C. and Nikolov, N. and Ricci, D. and Schaefer, S. and Schoenebeck, F. and Skottfelt, J. and Wertz, O. and Alsubai, K. A. and Bozza, V. and Browne, P. and Dodds, P. and Gu, S.-H. and Harpsoe, K. and Henning, Th and Hundertmark, M. and Jessen-Hansen, J. and Kains, N. and Kerins, E. and Kjeldsen, H. and Lund, M. N. and Lundkvist, M. and Madhusudhan, N. and Mathiasen, M. and Penny, M. T. and Proft, S. and Rahvar, S. and Sahu, K. and Scarpetta, G. and Snodgrass, C. and Surdej, J.}, url = {http://arxiv.org/abs/1306.6384}, doi = {10.1093/mnras/stt1394}, issn = {0035-8711, 1365-2966}, year = {2013}, date = {2013-11-01}, urldate = {2016-12-24}, journal = {Monthly Notices of the Royal Astronomical Society}, volume = {436}, number = {1}, pages = {2--18}, abstract = {We present new ground-based, multi-colour, broad-band photometric measurements of the physical parameters, transmission and emission spectra of the transiting extrasolar planet WASP-19b. The measurements are based on observations of 8 transits and four occultations using the 1.5m Danish Telescope, 14 transits at the PEST observatory, and 1 transit observed simultaneously through four optical and three near-infrared filters, using the GROND instrument on the ESO 2.2m telescope. We use these new data to measure refined physical parameters for the system. We find the planet to be more bloated and the system to be twice as old as initially thought. We also used published and archived datasets to study the transit timings, which do not depart from a linear ephemeris. We detected an anomaly in the GROND transit light curve which is compatible with a spot on the photosphere of the parent star. The starspot position, size, spot contrast and temperature were established. Using our new and published measurements, we assembled the planet's transmission spectrum over the 370-2350 nm wavelength range and its emission spectrum over the 750-8000 nm range. By comparing these data to theoretical models we investigated the theoretically-predicted variation of the apparent radius of WASP-19b as a function of wavelength and studied the composition and thermal structure of its atmosphere. We conclude that: there is no evidence for strong optical absorbers at low pressure, supporting the common idea that the planet's atmosphere lacks a dayside inversion; the temperature of the planet is not homogenized, because the high warming of its dayside causes the planet to be more efficient in re-radiating than redistributing energy to the night side; the planet seems to be outside of any current classification scheme.}, note = {arXiv: 1306.6384}, keywords = {}, pubstate = {published}, tppubtype = {article} } We present new ground-based, multi-colour, broad-band photometric measurements of the physical parameters, transmission and emission spectra of the transiting extrasolar planet WASP-19b. The measurements are based on observations of 8 transits and four occultations using the 1.5m Danish Telescope, 14 transits at the PEST observatory, and 1 transit observed simultaneously through four optical and three near-infrared filters, using the GROND instrument on the ESO 2.2m telescope. We use these new data to measure refined physical parameters for the system. We find the planet to be more bloated and the system to be twice as old as initially thought. We also used published and archived datasets to study the transit timings, which do not depart from a linear ephemeris. We detected an anomaly in the GROND transit light curve which is compatible with a spot on the photosphere of the parent star. The starspot position, size, spot contrast and temperature were established. Using our new and published measurements, we assembled the planet's transmission spectrum over the 370-2350 nm wavelength range and its emission spectrum over the 750-8000 nm range. By comparing these data to theoretical models we investigated the theoretically-predicted variation of the apparent radius of WASP-19b as a function of wavelength and studied the composition and thermal structure of its atmosphere. We conclude that: there is no evidence for strong optical absorbers at low pressure, supporting the common idea that the planet's atmosphere lacks a dayside inversion; the temperature of the planet is not homogenized, because the high warming of its dayside causes the planet to be more efficient in re-radiating than redistributing energy to the night side; the planet seems to be outside of any current classification scheme. |
| 12. | Gary, Bruce L., Tan, T. G., Curtis, Ivan, Tristram, Paul J., Fukui, Akihiko Searching for White Dwarf Exoplanets: WD 2359-434 Case Study Journal Article Society for Astronomical Sciences Annual Symposium, 32 , pp. 71–78, 2013. @article{gary_searching_2013, title = {Searching for White Dwarf Exoplanets: WD 2359-434 Case Study}, author = {Gary, Bruce L. and Tan, T. G. and Curtis, Ivan and Tristram, Paul J. and Fukui, Akihiko}, url = {http://adsabs.harvard.edu/abs/2013SASS...32...71G}, year = {2013}, date = {2013-05-01}, urldate = {2016-12-24}, journal = {Society for Astronomical Sciences Annual Symposium}, volume = {32}, pages = {71--78}, abstract = {The white dwarf WD 2359-434 was found to vary with a period of 2.695022 ± 0.000014 hours and semiamplitude of 0.00480 ± 0.00023 magnitude. One explanation for the variation is a starspot with a 3.8-degree radius (assuming 500 K cooler than the surroundings) at latitude of textasciitilde 27 degrees and a star rotation axis inclination of textasciitilde 30 degrees. The brightness variation was very close to sinusoidal, and there were no changes in amplitude, period or phase during the 1.1 years of observations. This permitted consideration of an alternative explanation: a Jupiter-size exoplanet that reflects the white dwarf's light in amounts that vary with orbital position. Follow-up observations are suggested for distinguishing between these two interpretations.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The white dwarf WD 2359-434 was found to vary with a period of 2.695022 ± 0.000014 hours and semiamplitude of 0.00480 ± 0.00023 magnitude. One explanation for the variation is a starspot with a 3.8-degree radius (assuming 500 K cooler than the surroundings) at latitude of textasciitilde 27 degrees and a star rotation axis inclination of textasciitilde 30 degrees. The brightness variation was very close to sinusoidal, and there were no changes in amplitude, period or phase during the 1.1 years of observations. This permitted consideration of an alternative explanation: a Jupiter-size exoplanet that reflects the white dwarf's light in amounts that vary with orbital position. Follow-up observations are suggested for distinguishing between these two interpretations. |
| 11. | Pastorello, A., Cappellaro, E., Inserra, C., Smartt, S. J., Pignata, G., Benetti, S., Valenti, S., Fraser, M., Takats, K., Benitez, S., Botticella, M. T., Brimacombe, J., Bufano, F., Cellier-Holzem, F., Costado, M. T., Cupani, G., Curtis, I., Elias-Rosa, N., Ergon, M., Fynbo, J. P. U., Hambsch, F.-J., Hamuy, M., Harutyunyan, A., Ivarson, K. M., Kankare, E., Martin, J. C., Kotak, R., LaCluyze, A. P., Maguire, K., Mattila, S., Maza, J., McCrum, M., Miluzio, M., Norgaard-Nielsen, H. U., Nysewander, M. C., Ochner, P., Pan, Y.-C., Pumo, M. L., Reichart, D. E., Tan, T. G., Taubenberger, S., Tomasella, L., Turatto, M., Wright, D. Interacting Supernovae and Supernova Impostors. SN 2009ip, is this the end? Journal Article The Astrophysical Journal, 767 (1), pp. 1, 2013, ISSN: 0004-637X, 1538-4357, (arXiv: 1210.3568). @article{pastorello_interacting_2013, title = {Interacting Supernovae and Supernova Impostors. SN 2009ip, is this the end?}, author = {Pastorello, A. and Cappellaro, E. and Inserra, C. and Smartt, S. J. and Pignata, G. and Benetti, S. and Valenti, S. and Fraser, M. and Takats, K. and Benitez, S. and Botticella, M. T. and Brimacombe, J. and Bufano, F. and Cellier-Holzem, F. and Costado, M. T. and Cupani, G. and Curtis, I. and Elias-Rosa, N. and Ergon, M. and Fynbo, J. P. U. and Hambsch, F.-J. and Hamuy, M. and Harutyunyan, A. and Ivarson, K. M. and Kankare, E. and Martin, J. C. and Kotak, R. and LaCluyze, A. P. and Maguire, K. and Mattila, S. and Maza, J. and McCrum, M. and Miluzio, M. and Norgaard-Nielsen, H. U. and Nysewander, M. C. and Ochner, P. and Pan, Y.-C. and Pumo, M. L. and Reichart, D. E. and Tan, T. G. and Taubenberger, S. and Tomasella, L. and Turatto, M. and Wright, D.}, url = {http://arxiv.org/abs/1210.3568}, doi = {10.1088/0004-637X/767/1/1}, issn = {0004-637X, 1538-4357}, year = {2013}, date = {2013-04-01}, urldate = {2016-12-24}, journal = {The Astrophysical Journal}, volume = {767}, number = {1}, pages = {1}, abstract = {We report the results of a 3 year-long dedicated monitoring campaign of a restless Luminous Blue Variable (LBV) in NGC 7259. The object, named SN 2009ip, was observed photometrically and spectroscopically in the optical and near-infrared domains. We monitored a number of erupting episodes in the past few years, and increased the density of our observations during eruptive episodes. In this paper we present the full historical data set from 2009-2012 with multi-wavelength dense coverage of the two high luminosity events between August - September 2012. We construct bolometric light curves and measure the total luminosities of these eruptive or explosive events. We label them the 2012a event (lasting textasciitilde50 days) with a peak of 3x10textasciicircum41 erg/s, and the 2012b event (14 day rise time, still ongoing) with a peak of 8x10textasciicircum42 erg/s. The latter event reached an absolute R-band magnitude of about -18, comparable to that of a core-collapse supernova (SN). Our historical monitoring has detected high-velocity spectral features (textasciitilde13000 km/s) in September 2011, one year before the current SN-like event. This implies that the detection of such high velocity outflows cannot, conclusively, point to a core-collapse SN origin. We suggest that the initial peak in the 2012a event was unlikely to be due to a faint core-collapse SN. We propose that the high intrinsic luminosity of the latest peak, the variability history of SN 2009ip, and the detection of broad spectral lines indicative of high-velocity ejecta are consistent with a pulsational pair-instability event, and that the star may have survived the last outburst. The question of the survival of the LBV progenitor star and its future fate remain open issues, only to be answered with future monitoring of this historically unique explosion.}, note = {arXiv: 1210.3568}, keywords = {}, pubstate = {published}, tppubtype = {article} } We report the results of a 3 year-long dedicated monitoring campaign of a restless Luminous Blue Variable (LBV) in NGC 7259. The object, named SN 2009ip, was observed photometrically and spectroscopically in the optical and near-infrared domains. We monitored a number of erupting episodes in the past few years, and increased the density of our observations during eruptive episodes. In this paper we present the full historical data set from 2009-2012 with multi-wavelength dense coverage of the two high luminosity events between August - September 2012. We construct bolometric light curves and measure the total luminosities of these eruptive or explosive events. We label them the 2012a event (lasting textasciitilde50 days) with a peak of 3x10textasciicircum41 erg/s, and the 2012b event (14 day rise time, still ongoing) with a peak of 8x10textasciicircum42 erg/s. The latter event reached an absolute R-band magnitude of about -18, comparable to that of a core-collapse supernova (SN). Our historical monitoring has detected high-velocity spectral features (textasciitilde13000 km/s) in September 2011, one year before the current SN-like event. This implies that the detection of such high velocity outflows cannot, conclusively, point to a core-collapse SN origin. We suggest that the initial peak in the 2012a event was unlikely to be due to a faint core-collapse SN. We propose that the high intrinsic luminosity of the latest peak, the variability history of SN 2009ip, and the detection of broad spectral lines indicative of high-velocity ejecta are consistent with a pulsational pair-instability event, and that the star may have survived the last outburst. The question of the survival of the LBV progenitor star and its future fate remain open issues, only to be answered with future monitoring of this historically unique explosion. |
| 10. | Han, C., Udalski, A., Choi, J.-Y., Yee, J. C., Gould, A., Christie, G., Tan, T.-G., Szymański, M. K., Kubiak, M., Soszyński, I., Pietrzyński, G., Poleski, R., Ulaczyk, K., Pietrukowicz, P., Kozłowski, S., Skowron, J., Wyrzykowski, Ł, Almeida, L. A., Batista, V., Depoy, D. L., Dong, Subo, Drummond, J., Gaudi, B. S., Hwang, K.-H., Jablonski, F., Jung, Y.-K., Lee, C.-U., Koo, J.-R., McCormick, J., Monard, L. A. G., Natusch, T., Ngan, H., Park, H., Pogge, R. W., Porritt, Ian, Shin, I.-G. The second multiple-planet system discovered by microlensing: OGLE-2012-BLG-0026Lb, c, a pair of jovian planets beyond the snow line Journal Article The Astrophysical Journal, 762 (2), pp. L28, 2013, ISSN: 2041-8205, 2041-8213, (arXiv: 1210.4265). @article{han_second_2013, title = {The second multiple-planet system discovered by microlensing: OGLE-2012-BLG-0026Lb, c, a pair of jovian planets beyond the snow line}, author = {Han, C. and Udalski, A. and Choi, J.-Y. and Yee, J. C. and Gould, A. and Christie, G. and Tan, T.-G. and Szymański, M. K. and Kubiak, M. and Soszyński, I. and Pietrzyński, G. and Poleski, R. and Ulaczyk, K. and Pietrukowicz, P. and Kozłowski, S. and Skowron, J. and Wyrzykowski, Ł and Almeida, L. A. and Batista, V. and Depoy, D. L. and Dong, Subo and Drummond, J. and Gaudi, B. S. and Hwang, K.-H. and Jablonski, F. and Jung, Y.-K. and Lee, C.-U. and Koo, J.-R. and McCormick, J. and Monard, L. A. G. and Natusch, T. and Ngan, H. and Park, H. and Pogge, R. W. and Porritt, Ian and Shin, I.-G.}, url = {http://arxiv.org/abs/1210.4265}, doi = {10.1088/2041-8205/762/2/L28}, issn = {2041-8205, 2041-8213}, year = {2013}, date = {2013-01-01}, urldate = {2016-12-24}, journal = {The Astrophysical Journal}, volume = {762}, number = {2}, pages = {L28}, abstract = {We report the discovery of a planetary system from observation of the high-magnification microlensing event OGLE-2012-BLG-0026. The lensing light curve exhibits a complex central perturbation with multiple features. We find that the perturbation was produced by two planets located near the Einstein ring of the planet host star. We identify 4 possible solutions resulting from the well-known close/wide degeneracy. By measuring both the lens parallax and the Einstein radius, we estimate the physical parameters of the planetary system. According to the best-fit model, the two planet masses are textasciitilde0.11 M_Jupiter and 0.68 M_Jupiter and they are orbiting a G-type main sequence star with a mass textasciitilde0.82 M_Sun. The projected separations of the individual planets are beyond the snow line in all four solutions, being textasciitilde3.8 AU and 4.6 AU in the best-fit solution. The deprojected separations are both individually larger and possibly reversed in order. This is the second multi-planet system with both planets beyond the snow line discovered by microlensing. This is the only such a system (other than the Solar System) with measured planet masses without sin(i) degeneracy. The planetary system is located at a distance 4.1 kpc from the Earth toward the Galactic center. It is very likely that extra light from stars other than the lensed star comes from the lens itself. If this is correct, it will be possible to obtain detailed information about the planet-host star from follow-up observation.}, note = {arXiv: 1210.4265}, keywords = {}, pubstate = {published}, tppubtype = {article} } We report the discovery of a planetary system from observation of the high-magnification microlensing event OGLE-2012-BLG-0026. The lensing light curve exhibits a complex central perturbation with multiple features. We find that the perturbation was produced by two planets located near the Einstein ring of the planet host star. We identify 4 possible solutions resulting from the well-known close/wide degeneracy. By measuring both the lens parallax and the Einstein radius, we estimate the physical parameters of the planetary system. According to the best-fit model, the two planet masses are textasciitilde0.11 M_Jupiter and 0.68 M_Jupiter and they are orbiting a G-type main sequence star with a mass textasciitilde0.82 M_Sun. The projected separations of the individual planets are beyond the snow line in all four solutions, being textasciitilde3.8 AU and 4.6 AU in the best-fit solution. The deprojected separations are both individually larger and possibly reversed in order. This is the second multi-planet system with both planets beyond the snow line discovered by microlensing. This is the only such a system (other than the Solar System) with measured planet masses without sin(i) degeneracy. The planetary system is located at a distance 4.1 kpc from the Earth toward the Galactic center. It is very likely that extra light from stars other than the lensed star comes from the lens itself. If this is correct, it will be possible to obtain detailed information about the planet-host star from follow-up observation. |
2012 |
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| 9. | Shin, I.-G., Han, C., Gould, A., Udalski, A., Sumi, T., Dominik, M., Beaulieu, J.-P., Tsapras, Y., Bozza, V., Szymański, M. K., Kubiak, M., Soszyński, I., Pietrzyński, G., Poleski, R., Ulaczyk, K., Pietrukowicz, P., Kozłowski, S., Skowron, J., Wyrzykowski, Ł, Abe, F., Bennett, D. P., Bond, I. A., Botzler, C. S., Freeman, M., Fukui, A., Furusawa, K., Hayashi, F., Hearnshaw, J. B., Hosaka, S., Itow, Y., Kamiya, K., Kilmartin, P. M., Kobara, S., Korpela, A., Lin, W., Ling, C. H., Makita, S., Masuda, K., Matsubara, Y., Miyake, N., Muraki, Y., Nagaya, M., Nishimoto, K., Ohnishi, K., Okumura, T., Omori, K., Perrott, Y. C., Rattenbury, N., Saito, To, Skuljan, L., Sullivan, D. J., Suzuki, D., Sweatman, W. L., Tristram, P. J., Wada, K., Yock, P. C. M., Christie, G. W., Depoy, D. L., Dong, S., Gal-Yam, A., Gaudi, B. S., Hung, L.-W., Janczak, J., Kaspi, S., Maoz, D., McCormick, J., McGregor, D., Moorhouse, D., Muñoz, J. A., Natusch, T., Nelson, C., Pogge, R. W., Tan, T.-G., Polishook, D., Shvartzvald, Y., Shporer, A., Thornley, G., Malamud, U., Yee, J. C., Choi, J.-Y., Jung, Y.-K., Park, H., Lee, C.-U., Park, B.-G., Koo, J.-R., Bajek, D., Bramich, D. M., Browne, P., Horne, K., Ipatov, S., Snodgrass, C., Steele, I., Street, R., Alsubai, K. A., Burgdorf, M. J., Novati, S. Calchi, Dodds, P., Dreizler, S., Fang, X.-S., Grundahl, F., Gu, C.-H., Hardis, S., Harpsøe, K., Hinse, T. C., Hundertmark, M., Jessen-Hansen, J., Jørgensen, U. G., Kains, N., Kerins, E., Liebig, C., Lund, M., Lundkvist, M., Mancini, L., Mathiasen, M., Hornstrup, A., Penny, M. T., Proft, S., Rahvar, S., Ricci, D., Scarpetta, G., Skottfelt, J., Southworth, J., Surdej, J., Tregloan-Reed, J., Wertz, O., Zimmer, F., Albrow, M. D., Batista, V., Brillant, S., Caldwell, J. A. R., Calitz, J. J., Cassan, A., Cole, A., Cook, K. H., Corrales, E., Coutures, Ch, Dieters, S., Prester, D. Dominis, Donatowicz, J., Fouqué, P., Greenhill, J., Hill, K., Hoffman, M., Kane, S. R., Kubas, D., Marquette, J.-B., Martin, R., Meintjes, P., Menzies, J., Pollard, K. R., Sahu, K. C., Wambsganss, J., Williams, A., Vinter, C., Zub, M. Microlensig Binaries with Candidate Brown Dwarf Companions Journal Article The Astrophysical Journal, 760 (2), pp. 116, 2012, ISSN: 0004-637X, 1538-4357, (arXiv: 1208.2323). @article{shin_microlensig_2012, title = {Microlensig Binaries with Candidate Brown Dwarf Companions}, author = {Shin, I.-G. and Han, C. and Gould, A. and Udalski, A. and Sumi, T. and Dominik, M. and Beaulieu, J.-P. and Tsapras, Y. and Bozza, V. and Szymański, M. K. and Kubiak, M. and Soszyński, I. and Pietrzyński, G. and Poleski, R. and Ulaczyk, K. and Pietrukowicz, P. and Kozłowski, S. and Skowron, J. and Wyrzykowski, Ł and Abe, F. and Bennett, D. P. and Bond, I. A. and Botzler, C. S. and Freeman, M. and Fukui, A. and Furusawa, K. and Hayashi, F. and Hearnshaw, J. B. and Hosaka, S. and Itow, Y. and Kamiya, K. and Kilmartin, P. M. and Kobara, S. and Korpela, A. and Lin, W. and Ling, C. H. and Makita, S. and Masuda, K. and Matsubara, Y. and Miyake, N. and Muraki, Y. and Nagaya, M. and Nishimoto, K. and Ohnishi, K. and Okumura, T. and Omori, K. and Perrott, Y. C. and Rattenbury, N. and Saito, To and Skuljan, L. and Sullivan, D. J. and Suzuki, D. and Sweatman, W. L. and Tristram, P. J. and Wada, K. and Yock, P. C. M. and Christie, G. W. and Depoy, D. L. and Dong, S. and Gal-Yam, A. and Gaudi, B. S. and Hung, L.-W. and Janczak, J. and Kaspi, S. and Maoz, D. and McCormick, J. and McGregor, D. and Moorhouse, D. and Muñoz, J. A. and Natusch, T. and Nelson, C. and Pogge, R. W. and Tan, T.-G. and Polishook, D. and Shvartzvald, Y. and Shporer, A. and Thornley, G. and Malamud, U. and Yee, J. C. and Choi, J.-Y. and Jung, Y.-K. and Park, H. and Lee, C.-U. and Park, B.-G. and Koo, J.-R. and Bajek, D. and Bramich, D. M. and Browne, P. and Horne, K. and Ipatov, S. and Snodgrass, C. and Steele, I. and Street, R. and Alsubai, K. A. and Burgdorf, M. J. and Novati, S. Calchi and Dodds, P. and Dreizler, S. and Fang, X.-S. and Grundahl, F. and Gu, C.-H. and Hardis, S. and Harpsøe, K. and Hinse, T. C. and Hundertmark, M. and Jessen-Hansen, J. and Jørgensen, U. G. and Kains, N. and Kerins, E. and Liebig, C. and Lund, M. and Lundkvist, M. and Mancini, L. and Mathiasen, M. and Hornstrup, A. and Penny, M. T. and Proft, S. and Rahvar, S. and Ricci, D. and Scarpetta, G. and Skottfelt, J. and Southworth, J. and Surdej, J. and Tregloan-Reed, J. and Wertz, O. and Zimmer, F. and Albrow, M. D. and Batista, V. and Brillant, S. and Caldwell, J. A. R. and Calitz, J. J. and Cassan, A. and Cole, A. and Cook, K. H. and Corrales, E. and Coutures, Ch and Dieters, S. and Prester, D. Dominis and Donatowicz, J. and Fouqué, P. and Greenhill, J. and Hill, K. and Hoffman, M. and Kane, S. R. and Kubas, D. and Marquette, J.-B. and Martin, R. and Meintjes, P. and Menzies, J. and Pollard, K. R. and Sahu, K. C. and Wambsganss, J. and Williams, A. and Vinter, C. and Zub, M.}, url = {http://arxiv.org/abs/1208.2323}, doi = {10.1088/0004-637X/760/2/116}, issn = {0004-637X, 1538-4357}, year = {2012}, date = {2012-12-01}, urldate = {2016-12-24}, journal = {The Astrophysical Journal}, volume = {760}, number = {2}, pages = {116}, abstract = {Brown dwarfs are important objects because they may provide a missing link between stars and planets, two populations that have dramatically different formation history. In this paper, we present the candidate binaries with brown dwarf companions that are found by analyzing binary microlensing events discovered during 2004 - 2011 observation seasons. Based on the low mass ratio criterion of q textless 0.2, we found 7 candidate events, including OGLE-2004-BLG-035, OGLE-2004-BLG-039, OGLE-2007-BLG-006, OGLE-2007-BLG-399/MOA-2007-BLG-334, MOA-2011-BLG-104/OGLE-2011-BLG-0172, MOA-2011-BLG-149, and MOA-201-BLG-278/OGLE-2011-BLG-012N. Among them, we are able to confirm that the companions of the lenses of MOA-2011-BLG-104/OGLE-2011-BLG-0172 and MOA-2011-BLG-149 are brown dwarfs by determining the mass of the lens based on the simultaneous measurement of the Einstein radius and the lens parallax. The measured mass of the brown dwarf companions are (0.02 +/- 0.01) M_Sun and (0.019 +/- 0.002) M_Sun for MOA-2011-BLG-104/OGLE-2011-BLG-0172 and MOA-2011-BLG-149, respectively, and both companions are orbiting low mass M dwarf host stars. More microlensing brown dwarfs are expected to be detected as the number of lensing events with well covered light curves increases with new generation searches.}, note = {arXiv: 1208.2323}, keywords = {}, pubstate = {published}, tppubtype = {article} } Brown dwarfs are important objects because they may provide a missing link between stars and planets, two populations that have dramatically different formation history. In this paper, we present the candidate binaries with brown dwarf companions that are found by analyzing binary microlensing events discovered during 2004 - 2011 observation seasons. Based on the low mass ratio criterion of q textless 0.2, we found 7 candidate events, including OGLE-2004-BLG-035, OGLE-2004-BLG-039, OGLE-2007-BLG-006, OGLE-2007-BLG-399/MOA-2007-BLG-334, MOA-2011-BLG-104/OGLE-2011-BLG-0172, MOA-2011-BLG-149, and MOA-201-BLG-278/OGLE-2011-BLG-012N. Among them, we are able to confirm that the companions of the lenses of MOA-2011-BLG-104/OGLE-2011-BLG-0172 and MOA-2011-BLG-149 are brown dwarfs by determining the mass of the lens based on the simultaneous measurement of the Einstein radius and the lens parallax. The measured mass of the brown dwarf companions are (0.02 +/- 0.01) M_Sun and (0.019 +/- 0.002) M_Sun for MOA-2011-BLG-104/OGLE-2011-BLG-0172 and MOA-2011-BLG-149, respectively, and both companions are orbiting low mass M dwarf host stars. More microlensing brown dwarfs are expected to be detected as the number of lensing events with well covered light curves increases with new generation searches. |
| 8. | Shin, I.-G., Han, C., Choi, J.-Y., Udalski, A., Sumi, T., Gould, A., Bozza, V., Dominik, M., Fouqué, P., Horne, K., M, Szymański, K., Kubiak, M., Soszyński, I., Pietrzyński, G., Poleski, R., Ulaczyk, K., Pietrukowicz, P., Kozłowski, S., Skowron, J., Wyrzykowski, Ł, Abe, F., Bennett, D. P., Bond, I. A., Botzler, C. S., Chote, P., Freeman, M., Fukui, A., Furusawa, K., Itow, Y., Kobara, S., Ling, C. H., Masuda, K., Matsubara, Y., Miyake, N., Muraki, Y., Ohmori, K., Ohnishi, K., Rattenbury, N. J., Saito, To, Sullivan, D. J., Suzuki, D., Suzuki, K., Sweatman, W. L., Takino, S., Tristram, P. J., Wada, K., Yock, P. C. M., Bramich, D. M., Snodgrass, C., Steele, I. A., Street, R. A., Tsapras, Y., Alsubai, K. A., Browne, P., Burgdorf, M. J., Novati, S. Calchi, Dodds, P., Dreizler, S., Fang, X.-S., Grundahl, F., Gu, C.-H., Hardis, S., Harpsøe, K., Hinse, T. C., Hornstrup, A., Hundertmark, M., Jessen-Hansen, J., Jørgensen, U. G., Kains, N., Kerins, E., Liebig, C., Lund, M., Lunkkvist, M., Mancini, L., Mathiasen, M., Penny, M. T., Rahvar, S., Ricci, D., Scarpetta, G., Skottfelt, J., Southworth, J., Surdej, J., Tregloan-Reed, J., Wambsganss, J., Wertz, O., Almeida, L. A., Batista, V., Christie, G., DePoy, D. L., Dong, Subo, Gaudi, B. S., Henderson, C., Jablonski, F., Lee, C.-U., McCormick, J., McGregor, D., Moorhouse, D., Natusch, T., Ngan, H., Park, S.-Y., Pogge, R. W., Tan, T.-G., Thornley, G., Yee, J. C., Albrow, M. D., Bachelet, E., Beaulieu, J.-P., Brillant, S., Cassan, A., Cole, A. A., Corrales, E., Coutures, C., Dieters, S., Prester, D. Dominis, Donatowicz, J., Greenhill, J., Kubas, D., Marquette, J.-B., Menzies, J. W., Sahu, K. C., Zub, M. Characterizing Low-Mass Binaries From Observation of Long Time-scale Caustic-crossing Gravitational Microlensing Events Journal Article The Astrophysical Journal, 755 (2), pp. 91, 2012, ISSN: 0004-637X, 1538-4357, (arXiv: 1204.2869). @article{shin_characterizing_2012, title = {Characterizing Low-Mass Binaries From Observation of Long Time-scale Caustic-crossing Gravitational Microlensing Events}, author = {Shin, I.-G. and Han, C. and Choi, J.-Y. and Udalski, A. and Sumi, T. and Gould, A. and Bozza, V. and Dominik, M. and Fouqué, P. and Horne, K. and M and Szymański, K. and Kubiak, M. and Soszyński, I. and Pietrzyński, G. and Poleski, R. and Ulaczyk, K. and Pietrukowicz, P. and Kozłowski, S. and Skowron, J. and Wyrzykowski, Ł and Abe, F. and Bennett, D. P. and Bond, I. A. and Botzler, C. S. and Chote, P. and Freeman, M. and Fukui, A. and Furusawa, K. and Itow, Y. and Kobara, S. and Ling, C. H. and Masuda, K. and Matsubara, Y. and Miyake, N. and Muraki, Y. and Ohmori, K. and Ohnishi, K. and Rattenbury, N. J. and Saito, To and Sullivan, D. J. and Suzuki, D. and Suzuki, K. and Sweatman, W. L. and Takino, S. and Tristram, P. J. and Wada, K. and Yock, P. C. M. and Bramich, D. M. and Snodgrass, C. and Steele, I. A. and Street, R. A. and Tsapras, Y. and Alsubai, K. A. and Browne, P. and Burgdorf, M. J. and Novati, S. Calchi and Dodds, P. and Dreizler, S. and Fang, X.-S. and Grundahl, F. and Gu, C.-H. and Hardis, S. and Harpsøe, K. and Hinse, T. C. and Hornstrup, A. and Hundertmark, M. and Jessen-Hansen, J. and Jørgensen, U. G. and Kains, N. and Kerins, E. and Liebig, C. and Lund, M. and Lunkkvist, M. and Mancini, L. and Mathiasen, M. and Penny, M. T. and Rahvar, S. and Ricci, D. and Scarpetta, G. and Skottfelt, J. and Southworth, J. and Surdej, J. and Tregloan-Reed, J. and Wambsganss, J. and Wertz, O. and Almeida, L. A. and Batista, V. and Christie, G. and DePoy, D. L. and Dong, Subo and Gaudi, B. S. and Henderson, C. and Jablonski, F. and Lee, C.-U. and McCormick, J. and McGregor, D. and Moorhouse, D. and Natusch, T. and Ngan, H. and Park, S.-Y. and Pogge, R. W. and Tan, T.-G. and Thornley, G. and Yee, J. C. and Albrow, M. D. and Bachelet, E. and Beaulieu, J.-P. and Brillant, S. and Cassan, A. and Cole, A. A. and Corrales, E. and Coutures, C. and Dieters, S. and Prester, D. Dominis and Donatowicz, J. and Greenhill, J. and Kubas, D. and Marquette, J.-B. and Menzies, J. W. and Sahu, K. C. and Zub, M.}, url = {http://arxiv.org/abs/1204.2869}, doi = {10.1088/0004-637X/755/2/91}, issn = {0004-637X, 1538-4357}, year = {2012}, date = {2012-08-01}, urldate = {2016-12-24}, journal = {The Astrophysical Journal}, volume = {755}, number = {2}, pages = {91}, abstract = {Despite astrophysical importance of binary star systems, detections are limited to those located in small ranges of separations, distances, and masses and thus it is necessary to use a variety of observational techniques for a complete view of stellar multiplicity across a broad range of physical parameters. In this paper, we report the detections and measurements of 2 binaries discovered from observations of microlensing events MOA-2011-BLG-090 and OGLE-2011-BLG-0417. Determinations of the binary masses are possible by simultaneously measuring the Einstein radius and the lens parallax. The measured masses of the binary components are 0.43 $M_textbackslashodot$ and 0.39 $M_textbackslashodot$ for MOA-2011-BLG-090 and 0.57 $M_textbackslashodot$ and 0.17 $M_textbackslashodot$ for OGLE-2011-BLG-0417 and thus both lens components of MOA-2011-BLG-090 and one component of OGLE-2011-BLG-0417 are M dwarfs, demonstrating the usefulness of microlensing in detecting binaries composed of low-mass components. From modeling of the light curves considering full Keplerian motion of the lens, we also measure the orbital parameters of the binaries. The blended light of OGLE-2011-BLG-0417 comes very likely from the lens itself, making it possible to check the microlensing orbital solution by follow-up radial-velocity observation. For both events, the caustic-crossing parts of the light curves, which are critical for determining the physical lens parameters, were resolved by high-cadence survey observations and thus it is expected that the number of microlensing binaries with measured physical parameters will increase in the future.}, note = {arXiv: 1204.2869}, keywords = {}, pubstate = {published}, tppubtype = {article} } Despite astrophysical importance of binary star systems, detections are limited to those located in small ranges of separations, distances, and masses and thus it is necessary to use a variety of observational techniques for a complete view of stellar multiplicity across a broad range of physical parameters. In this paper, we report the detections and measurements of 2 binaries discovered from observations of microlensing events MOA-2011-BLG-090 and OGLE-2011-BLG-0417. Determinations of the binary masses are possible by simultaneously measuring the Einstein radius and the lens parallax. The measured masses of the binary components are 0.43 $M_textbackslashodot$ and 0.39 $M_textbackslashodot$ for MOA-2011-BLG-090 and 0.57 $M_textbackslashodot$ and 0.17 $M_textbackslashodot$ for OGLE-2011-BLG-0417 and thus both lens components of MOA-2011-BLG-090 and one component of OGLE-2011-BLG-0417 are M dwarfs, demonstrating the usefulness of microlensing in detecting binaries composed of low-mass components. From modeling of the light curves considering full Keplerian motion of the lens, we also measure the orbital parameters of the binaries. The blended light of OGLE-2011-BLG-0417 comes very likely from the lens itself, making it possible to check the microlensing orbital solution by follow-up radial-velocity observation. For both events, the caustic-crossing parts of the light curves, which are critical for determining the physical lens parameters, were resolved by high-cadence survey observations and thus it is expected that the number of microlensing binaries with measured physical parameters will increase in the future. |
| 7. | Yee, J. C., Shvartzvald, Y., Gal-Yam, A., Bond, I. A., Udalski, A., Kozlowski, S., Han, C., Gould, A., Skowron, J., Suzuki, D., Collaboration, the MOA, Collaboration, the OGLE, Collaboration, the MicroFUN MOA-2011-BLG-293Lb: A test of pure survey microlensing planet detections Journal Article The Astrophysical Journal, 755 (2), pp. 102, 2012, ISSN: 0004-637X, 1538-4357, (arXiv: 1201.1002). @article{yee_moa-2011-blg-293lb:_2012, title = {MOA-2011-BLG-293Lb: A test of pure survey microlensing planet detections}, author = {Yee, J. C. and Shvartzvald, Y. and Gal-Yam, A. and Bond, I. A. and Udalski, A. and Kozlowski, S. and Han, C. and Gould, A. and Skowron, J. and Suzuki, D. and Collaboration, the MOA and Collaboration, the OGLE and Collaboration, the MicroFUN}, url = {http://arxiv.org/abs/1201.1002}, doi = {10.1088/0004-637X/755/2/102}, issn = {0004-637X, 1538-4357}, year = {2012}, date = {2012-08-01}, urldate = {2016-12-24}, journal = {The Astrophysical Journal}, volume = {755}, number = {2}, pages = {102}, abstract = {Because of the development of large-format, wide-field cameras, microlensing surveys are now able to monitor millions of stars with sufficient cadence to detect planets. These new discoveries will span the full range of significance levels including planetary signals too small to be distinguished from the noise. At present, we do not understand where the threshold is for detecting planets. MOA-2011-BLG-293Lb is the first planet to be published from the new surveys, and it also has substantial followup observations. This planet is robustly detected in survey+followup data (Delta chitextasciicircum2 textasciitilde 5400). The planet/host mass ratio is q=5.3+/- 0.2*10textasciicircum-3. The best fit projected separation is s=0.548+/- 0.005 Einstein radii. However, due to the s--textgreaterstextasciicircum-1 degeneracy, projected separations of stextasciicircum-1 are only marginally disfavored at Delta chitextasciicircum2=3. A Bayesian estimate of the host mass gives M_L = 0.43textasciicircum+0.27_-0.17 M_Sun, with a sharp upper limit of M_L textless 1.2 M_Sun from upper limits on the lens flux. Hence, the planet mass is m_p=2.4textasciicircum+1.5_-0.9 M_Jup, and the physical projected separation is either r_perp = textasciitilde1.0 AU or r_perp = textasciitilde3.4 AU. We show that survey data alone predict this solution and are able to characterize the planet, but the Delta chitextasciicircum2 is much smaller (Delta chitextasciicircum2textasciitilde500) than with the followup data. The Delta chitextasciicircum2 for the survey data alone is smaller than for any other securely detected planet. This event suggests a means to probe the detection threshold, by analyzing a large sample of events like MOA-2011-BLG-293, which have both followup data and high cadence survey data, to provide a guide for the interpretation of pure survey microlensing data.}, note = {arXiv: 1201.1002}, keywords = {}, pubstate = {published}, tppubtype = {article} } Because of the development of large-format, wide-field cameras, microlensing surveys are now able to monitor millions of stars with sufficient cadence to detect planets. These new discoveries will span the full range of significance levels including planetary signals too small to be distinguished from the noise. At present, we do not understand where the threshold is for detecting planets. MOA-2011-BLG-293Lb is the first planet to be published from the new surveys, and it also has substantial followup observations. This planet is robustly detected in survey+followup data (Delta chitextasciicircum2 textasciitilde 5400). The planet/host mass ratio is q=5.3+/- 0.2*10textasciicircum-3. The best fit projected separation is s=0.548+/- 0.005 Einstein radii. However, due to the s--textgreaterstextasciicircum-1 degeneracy, projected separations of stextasciicircum-1 are only marginally disfavored at Delta chitextasciicircum2=3. A Bayesian estimate of the host mass gives M_L = 0.43textasciicircum+0.27_-0.17 M_Sun, with a sharp upper limit of M_L textless 1.2 M_Sun from upper limits on the lens flux. Hence, the planet mass is m_p=2.4textasciicircum+1.5_-0.9 M_Jup, and the physical projected separation is either r_perp = textasciitilde1.0 AU or r_perp = textasciitilde3.4 AU. We show that survey data alone predict this solution and are able to characterize the planet, but the Delta chitextasciicircum2 is much smaller (Delta chitextasciicircum2textasciitilde500) than with the followup data. The Delta chitextasciicircum2 for the survey data alone is smaller than for any other securely detected planet. This event suggests a means to probe the detection threshold, by analyzing a large sample of events like MOA-2011-BLG-293, which have both followup data and high cadence survey data, to provide a guide for the interpretation of pure survey microlensing data. |
| 6. | Choi, J.-Y., Shin, I.-G., Park, S.-Y., Han, C., Gould, A., Sumi, T., Udalski, A., Beaulieu, J.-P., Street, R., Dominik, M., Allen, W., Almeida, L. A., Bos, M., Christie, G. W., Depoy, D. L., Dong, S., Drummond, J., Gal-Yam, A., Gaudi, B. S., Henderson, C. B., Hung, L.-W., Jablonski, F., Janczak, J., Lee, C.-U., Mallia, F., Maury, A., McCormick, J., McGregor, D., Monard, L. A. G., Moorhouse, D., Muñoz, J. A., Natusch, T., Nelson, C., Park, B.-G., Pogge, R. W., Tan, T.-G. "TG", Thornley, G., Yee, J. C., Abe, F., Barnard, E., Baudry, J., Bennett, D. P., Bond, I. A., Botzler, C. S., Freeman, M., Fukui, A., Furusawa, K., Hayashi, F., Hearnshaw, J. B., Hosaka, S., Itow, Y., Kamiya, K., Kilmartin, P. M., Kobara, S., Korpela, A., Lin, W., Ling, C. H., Makita, S., Masuda, K., Matsubara, Y., Miyake, N., Muraki, Y., Nagaya, M., Nishimoto, K., Ohnishi, K., Okumura, T., Omori, K., Perrott, Y. C., Rattenbury, N., Saito, To, Skuljan, L., Sullivan, D. J., Suzuki, D., Suzuki, K., Sweatman, W. L., Takino, S., Tristram, P. J., Wada, K., Yock, P. C. M., Szymański, M. K., Kubiak, M., Pietrzyński, G., Soszyński, I., Poleski, R., Ulaczyk, K., Wyrzykowski, Ł, Kozłowski, S., Pietrukowicz, P., Albrow, M. D., Bachelet, E., Batista, V., Bennett, C. S., Bowens-Rubin, R., Brillant, S., Cassan, A., Cole, A., Corrales, E., Coutures, Ch, Dieters, S., Prester, D. Dominis, Donatowicz, J., Fouqué, P., Greenhill, J., Kane, S. R., Menzies, J., Sahu, K. C., Wambsganss, J., Williams, A., Zub, M., Allan, A., Bramich, D. M., Browne, P., Clay, N., Fraser, S., Horne, K., Kains, N., Mottram, C., Snodgrass, C., Steele, I., Tsapras, Y., Alsubai, K. A., Bozza, V., Burgdorf, M. J., Novati, S. Calchi, Dodds, P., Dreizler, S., Finet, F., Gerner, T., Glitrup, M., Grundahl, F., Hardis, S., Harpsøe, K., Hinse, T. C., Hundertmark, M., Jørgensen, U. G., Kerins, E., Liebig, C., Maier, G., Mancini, L., Mathiasen, M., Penny, M. T., Proft, S., Rahvar, S., Ricci, D., Scarpetta, G., Schäfer, S., Schönebeck, F., Skottfelt, J., Surdej, J., Southworth, J., Zimmer, F. Characterizing Lenses and Lensed Stars of High-Magnification Single-lens Gravitational Microlensing Events With Lenses Passing Over Source Stars Journal Article The Astrophysical Journal, 751 (1), pp. 41, 2012, ISSN: 0004-637X, 1538-4357, (arXiv: 1111.4032). @article{choi_characterizing_2012, title = {Characterizing Lenses and Lensed Stars of High-Magnification Single-lens Gravitational Microlensing Events With Lenses Passing Over Source Stars}, author = {Choi, J.-Y. and Shin, I.-G. and Park, S.-Y. and Han, C. and Gould, A. and Sumi, T. and Udalski, A. and Beaulieu, J.-P. and Street, R. and Dominik, M. and Allen, W. and Almeida, L. A. and Bos, M. and Christie, G. W. and Depoy, D. L. and Dong, S. and Drummond, J. and Gal-Yam, A. and Gaudi, B. S. and Henderson, C. B. and Hung, L.-W. and Jablonski, F. and Janczak, J. and Lee, C.-U. and Mallia, F. and Maury, A. and McCormick, J. and McGregor, D. and Monard, L. A. G. and Moorhouse, D. and Muñoz, J. A. and Natusch, T. and Nelson, C. and Park, B.-G. and Pogge, R. W. and Tan, T.-G. "TG" and Thornley, G. and Yee, J. C. and Abe, F. and Barnard, E. and Baudry, J. and Bennett, D. P. and Bond, I. A. and Botzler, C. S. and Freeman, M. and Fukui, A. and Furusawa, K. and Hayashi, F. and Hearnshaw, J. B. and Hosaka, S. and Itow, Y. and Kamiya, K. and Kilmartin, P. M. and Kobara, S. and Korpela, A. and Lin, W. and Ling, C. H. and Makita, S. and Masuda, K. and Matsubara, Y. and Miyake, N. and Muraki, Y. and Nagaya, M. and Nishimoto, K. and Ohnishi, K. and Okumura, T. and Omori, K. and Perrott, Y. C. and Rattenbury, N. and Saito, To and Skuljan, L. and Sullivan, D. J. and Suzuki, D. and Suzuki, K. and Sweatman, W. L. and Takino, S. and Tristram, P. J. and Wada, K. and Yock, P. C. M. and Szymański, M. K. and Kubiak, M. and Pietrzyński, G. and Soszyński, I. and Poleski, R. and Ulaczyk, K. and Wyrzykowski, Ł and Kozłowski, S. and Pietrukowicz, P. and Albrow, M. D. and Bachelet, E. and Batista, V. and Bennett, C. S. and Bowens-Rubin, R. and Brillant, S. and Cassan, A. and Cole, A. and Corrales, E. and Coutures, Ch and Dieters, S. and Prester, D. Dominis and Donatowicz, J. and Fouqué, P. and Greenhill, J. and Kane, S. R. and Menzies, J. and Sahu, K. C. and Wambsganss, J. and Williams, A. and Zub, M. and Allan, A. and Bramich, D. M. and Browne, P. and Clay, N. and Fraser, S. and Horne, K. and Kains, N. and Mottram, C. and Snodgrass, C. and Steele, I. and Tsapras, Y. and Alsubai, K. A. and Bozza, V. and Burgdorf, M. J. and Novati, S. Calchi and Dodds, P. and Dreizler, S. and Finet, F. and Gerner, T. and Glitrup, M. and Grundahl, F. and Hardis, S. and Harpsøe, K. and Hinse, T. C. and Hundertmark, M. and Jørgensen, U. G. and Kerins, E. and Liebig, C. and Maier, G. and Mancini, L. and Mathiasen, M. and Penny, M. T. and Proft, S. and Rahvar, S. and Ricci, D. and Scarpetta, G. and Schäfer, S. and Schönebeck, F. and Skottfelt, J. and Surdej, J. and Southworth, J. and Zimmer, F.}, url = {http://arxiv.org/abs/1111.4032}, doi = {10.1088/0004-637X/751/1/41}, issn = {0004-637X, 1538-4357}, year = {2012}, date = {2012-05-01}, urldate = {2016-12-24}, journal = {The Astrophysical Journal}, volume = {751}, number = {1}, pages = {41}, abstract = {We present the analysis of the light curves of 9 high-magnification single-lens gravitational microlensing events with lenses passing over source stars, including OGLE-2004-BLG-254, MOA-2007-BLG-176, MOA-2007-BLG-233/OGLE-2007-BLG-302, MOA-2009-BLG-174, MOA-2010-BLG-436, MOA-2011-BLG-093, MOA-2011-BLG-274, OGLE-2011-BLG-0990/MOA-2011-BLG-300, and OGLE-2011-BLG-1101/MOA-2011-BLG-325. For all events, we measure the linear limb-darkening coefficients of the surface brightness profile of source stars by measuring the deviation of the light curves near the peak affected by the finite-source effect. For 7 events, we measure the Einstein radii and the lens-source relative proper motions. Among them, 5 events are found to have Einstein radii less than 0.2 mas, making the lenses candidates of very low-mass stars or brown dwarfs. For MOA-2011-BLG-274, especially, the small Einstein radius of $textbackslashtheta_textbackslashrm Etextbackslashsim 0.08$ mas combined with the short time scale of $t_textbackslashrm Etextbackslashsim 2.7$ days suggests the possibility that the lens is a free-floating planet. For MOA-2009-BLG-174, we measure the lens parallax and thus uniquely determine the physical parameters of the lens. We also find that the measured lens mass of $textbackslashsim 0.84textbackslash M_textbackslashodot$ is consistent with that of a star blended with the source, suggesting that the blend is likely to be the lens. Although we find planetary signals for none of events, we provide exclusion diagrams showing the confidence levels excluding the existence of a planet as a function of the separation and mass ratio.}, note = {arXiv: 1111.4032}, keywords = {}, pubstate = {published}, tppubtype = {article} } We present the analysis of the light curves of 9 high-magnification single-lens gravitational microlensing events with lenses passing over source stars, including OGLE-2004-BLG-254, MOA-2007-BLG-176, MOA-2007-BLG-233/OGLE-2007-BLG-302, MOA-2009-BLG-174, MOA-2010-BLG-436, MOA-2011-BLG-093, MOA-2011-BLG-274, OGLE-2011-BLG-0990/MOA-2011-BLG-300, and OGLE-2011-BLG-1101/MOA-2011-BLG-325. For all events, we measure the linear limb-darkening coefficients of the surface brightness profile of source stars by measuring the deviation of the light curves near the peak affected by the finite-source effect. For 7 events, we measure the Einstein radii and the lens-source relative proper motions. Among them, 5 events are found to have Einstein radii less than 0.2 mas, making the lenses candidates of very low-mass stars or brown dwarfs. For MOA-2011-BLG-274, especially, the small Einstein radius of $textbackslashtheta_textbackslashrm Etextbackslashsim 0.08$ mas combined with the short time scale of $t_textbackslashrm Etextbackslashsim 2.7$ days suggests the possibility that the lens is a free-floating planet. For MOA-2009-BLG-174, we measure the lens parallax and thus uniquely determine the physical parameters of the lens. We also find that the measured lens mass of $textbackslashsim 0.84textbackslash M_textbackslashodot$ is consistent with that of a star blended with the source, suggesting that the blend is likely to be the lens. Although we find planetary signals for none of events, we provide exclusion diagrams showing the confidence levels excluding the existence of a planet as a function of the separation and mass ratio. |
| 5. | Choi, J.-Y., Shin, I.-G., Han, C., Udalski, A., Sumi, T., Gould, A., Bozza, V., Dominik, M., Fouqué, P., Horne, K., Szymański, M. K., Kubiak, M., Soszyński, I., Pietrzyński, G., Poleski, R., Ulaczyk, K., Pietrukowicz, P., Kozłowski, S., Skowron, J., Wyrzykowski, Ł, Abe, F., Bennett, D. P., Bond, I. A., Botzler, C. S., Chote, P., Freeman, M., Fukui, A., Furusawa, K., Itow, Y., Kobara, S., Ling, C. H., Masuda, K., Matsubara, Y., Miyake, N., Muraki, Y., Ohmori, K., Ohnishi, K., Rattenbury, N. J., Saito, To, Sullivan, D. J., Suzuki, D., Suzuki, K., Sweatman, W. L., Takino, S., Tristram, P. J., Wada, K., Yock, P. C. M., Bramich, D. M., Snodgrass, C., Steele, I. A., Street, R. A., Tsapras, Y., Alsubai, K. A., Browne, P., Burgdorf, M. J., Novati, S. Calchi, Dodds, P., Dreizler, S., Fang, X.-S., Grundahl, F., Gu, C.-H., Hardis, S., Harpsøe, K., Hinse, T. C., Hornstrup, A., Hundertmark, M., Jessen-Hansen, J., Jørgensen, U. G., Kains, N., Kerins, E., Liebig, C., Lund, M., Lunkkvist, M., Mancini, L., Mathiasen, M., Penny, M. T., Rahvar, S., Ricci, D., Scarpetta, G., Skottfelt, J., Southworth, J., Surdej, J., Tregloan-Reed, J., Wambsganss, J., Wertz, O., Almeida, L. A., Batista, V., Christie, G., DePoy, D. L., Dong, Subo, Gaudi, B. S., Henderson, C., Jablonski, F., Lee, C.-U., McCormick, J., McGregor, D., Moorhouse, D., Natusch, T., Ngan, H., Park, S.-Y., Pogge, R. W., Tan, T.-G., Thornley, G., Yee, J. C., Albrow, M. D., Bachelet, E., Beaulieu, J.-P., Brillant, S., Cassan, A., Cole, A. A., Corrales, E., Coutures, C., Dieters, S., Prester, D. Dominis, Donatowicz, J., Greenhill, J., Kubas, D., Marquette, J.-B., Menzies, J. W., Sahu, K. C., Zub, M. ApJ, 756 (1), pp. 48, 2012, ISSN: 0004-637X, 1538-4357, (arXiv: 1204.4789). @article{choi_new_2012, title = {A New Type of Ambiguity in the Planet and Binary Interpretations of Central Perturbations of High-Magnification Gravitational Microlensing Events}, author = {Choi, J.-Y. and Shin, I.-G. and Han, C. and Udalski, A. and Sumi, T. and Gould, A. and Bozza, V. and Dominik, M. and Fouqué, P. and Horne, K. and Szymański, M. K. and Kubiak, M. and Soszyński, I. and Pietrzyński, G. and Poleski, R. and Ulaczyk, K. and Pietrukowicz, P. and Kozłowski, S. and Skowron, J. and Wyrzykowski, Ł and Abe, F. and Bennett, D. P. and Bond, I. A. and Botzler, C. S. and Chote, P. and Freeman, M. and Fukui, A. and Furusawa, K. and Itow, Y. and Kobara, S. and Ling, C. H. and Masuda, K. and Matsubara, Y. and Miyake, N. and Muraki, Y. and Ohmori, K. and Ohnishi, K. and Rattenbury, N. J. and Saito, To and Sullivan, D. J. and Suzuki, D. and Suzuki, K. and Sweatman, W. L. and Takino, S. and Tristram, P. J. and Wada, K. and Yock, P. C. M. and Bramich, D. M. and Snodgrass, C. and Steele, I. A. and Street, R. A. and Tsapras, Y. and Alsubai, K. A. and Browne, P. and Burgdorf, M. J. and Novati, S. Calchi and Dodds, P. and Dreizler, S. and Fang, X.-S. and Grundahl, F. and Gu, C.-H. and Hardis, S. and Harpsøe, K. and Hinse, T. C. and Hornstrup, A. and Hundertmark, M. and Jessen-Hansen, J. and Jørgensen, U. G. and Kains, N. and Kerins, E. and Liebig, C. and Lund, M. and Lunkkvist, M. and Mancini, L. and Mathiasen, M. and Penny, M. T. and Rahvar, S. and Ricci, D. and Scarpetta, G. and Skottfelt, J. and Southworth, J. and Surdej, J. and Tregloan-Reed, J. and Wambsganss, J. and Wertz, O. and Almeida, L. A. and Batista, V. and Christie, G. and DePoy, D. L. and Dong, Subo and Gaudi, B. S. and Henderson, C. and Jablonski, F. and Lee, C.-U. and McCormick, J. and McGregor, D. and Moorhouse, D. and Natusch, T. and Ngan, H. and Park, S.-Y. and Pogge, R. W. and Tan, T.-G. and Thornley, G. and Yee, J. C. and Albrow, M. D. and Bachelet, E. and Beaulieu, J.-P. and Brillant, S. and Cassan, A. and Cole, A. A. and Corrales, E. and Coutures, C. and Dieters, S. and Prester, D. Dominis and Donatowicz, J. and Greenhill, J. and Kubas, D. and Marquette, J.-B. and Menzies, J. W. and Sahu, K. C. and Zub, M.}, url = {http://arxiv.org/abs/1204.4789}, doi = {10.1088/0004-637X/756/1/48}, issn = {0004-637X, 1538-4357}, year = {2012}, date = {2012-01-01}, urldate = {2019-10-29}, journal = {ApJ}, volume = {756}, number = {1}, pages = {48}, abstract = {High-magnification microlensing events provide an important channel to detect planets. Perturbations near the peak of a high-magnification event can be produced either by a planet or a binary companion. It is known that central perturbations induced by both types of companions can be generally distinguished due to the basically different magnification pattern around caustics. In this paper, we present a case of central perturbations for which it is difficult to distinguish the planetary and binary interpretations. The peak of a lensing light curve affected by this perturbation appears to be blunt and flat. For a planetary case, this perturbation occurs when the source trajectory passes the negative perturbation region behind the back end of an arrowhead-shaped central caustic. For a binary case, a similar perturbation occurs for a source trajectory passing through the negative perturbation region between two cusps of an astroid-shaped caustic. We demonstrate the degeneracy for 2 high-magnification events of OGLE-2011-BLG-0526 and OGLE-2011-BLG-0950/MOA-2011-BLG-336. For OGLE-2011-BLG-0526, the $textbackslashchitextasciicircum2$ difference between the planetary and binary model is $textbackslashsim$ 3, implying that the degeneracy is very severe. For OGLE-2011-BLG-0950/MOA-2011-BLG-336, the stellar binary model is formally excluded with $textbackslashDelta textbackslashchitextasciicircum2 textbackslashsim$ 105 and the planetary model is preferred. However, it is difficult to claim a planet discovery because systematic residuals of data from the planetary model are larger than the difference between the planetary and binary models. Considering that 2 events observed during a single season suffer from such a degeneracy, it is expected that central perturbations experiencing this type of degeneracy is common.}, note = {arXiv: 1204.4789}, keywords = {}, pubstate = {published}, tppubtype = {article} } High-magnification microlensing events provide an important channel to detect planets. Perturbations near the peak of a high-magnification event can be produced either by a planet or a binary companion. It is known that central perturbations induced by both types of companions can be generally distinguished due to the basically different magnification pattern around caustics. In this paper, we present a case of central perturbations for which it is difficult to distinguish the planetary and binary interpretations. The peak of a lensing light curve affected by this perturbation appears to be blunt and flat. For a planetary case, this perturbation occurs when the source trajectory passes the negative perturbation region behind the back end of an arrowhead-shaped central caustic. For a binary case, a similar perturbation occurs for a source trajectory passing through the negative perturbation region between two cusps of an astroid-shaped caustic. We demonstrate the degeneracy for 2 high-magnification events of OGLE-2011-BLG-0526 and OGLE-2011-BLG-0950/MOA-2011-BLG-336. For OGLE-2011-BLG-0526, the $textbackslashchitextasciicircum2$ difference between the planetary and binary model is $textbackslashsim$ 3, implying that the degeneracy is very severe. For OGLE-2011-BLG-0950/MOA-2011-BLG-336, the stellar binary model is formally excluded with $textbackslashDelta textbackslashchitextasciicircum2 textbackslashsim$ 105 and the planetary model is preferred. However, it is difficult to claim a planet discovery because systematic residuals of data from the planetary model are larger than the difference between the planetary and binary models. Considering that 2 events observed during a single season suffer from such a degeneracy, it is expected that central perturbations experiencing this type of degeneracy is common. |
2011 |
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| 4. | Schaefer, Bradley E., Pagnotta, Ashley, LaCluyze, Aaron, Reichart, Daniel E., Ivarsen, Kevin M., Haislip, Joshua B., Nysewander, Melissa C., Moore, Justin P., Oksanen, Arto, Worters, Hannah L., Sefako, Ramotholo R., Mentz, Jaco, Dvorak, Shawn, Gomez, Tomas, Harris, Barbara G., Henden, Arne, Tan, Thiam Guan, Templeton, Matthew, Allen, W. H., Monard, Berto, Rea, Robert D., Roberts, George, Stein, William, Maehara, Hiroyuki, Richards, Thomas, Stockdale, Chris, Krajci, Tom, Sjoberg, George, McCormick, Jennie, Revnivtsev, Mikhail, Molkov, Sergei, Suleimanov, Valery, Darnley, Matthew J., Bode, Michael F., Handler, Gerald, Lepine, Sebastien, Shara, Michael Eclipses During the 2010 Eruption of the Recurrent Nova U Scorpii Journal Article The Astrophysical Journal, 742 (2), pp. 113, 2011, ISSN: 0004-637X, 1538-4357, (arXiv: 1108.1214). @article{schaefer_eclipses_2011, title = {Eclipses During the 2010 Eruption of the Recurrent Nova U Scorpii}, author = {Schaefer, Bradley E. and Pagnotta, Ashley and LaCluyze, Aaron and Reichart, Daniel E. and Ivarsen, Kevin M. and Haislip, Joshua B. and Nysewander, Melissa C. and Moore, Justin P. and Oksanen, Arto and Worters, Hannah L. and Sefako, Ramotholo R. and Mentz, Jaco and Dvorak, Shawn and Gomez, Tomas and Harris, Barbara G. and Henden, Arne and Tan, Thiam Guan and Templeton, Matthew and Allen, W. H. and Monard, Berto and Rea, Robert D. and Roberts, George and Stein, William and Maehara, Hiroyuki and Richards, Thomas and Stockdale, Chris and Krajci, Tom and Sjoberg, George and McCormick, Jennie and Revnivtsev, Mikhail and Molkov, Sergei and Suleimanov, Valery and Darnley, Matthew J. and Bode, Michael F. and Handler, Gerald and Lepine, Sebastien and Shara, Michael}, url = {http://arxiv.org/abs/1108.1214}, doi = {10.1088/0004-637X/742/2/113}, issn = {0004-637X, 1538-4357}, year = {2011}, date = {2011-12-01}, urldate = {2016-12-24}, journal = {The Astrophysical Journal}, volume = {742}, number = {2}, pages = {113}, abstract = {The eruption of the recurrent nova U Scorpii on 28 January 2010 is now the all-time best observed nova event. We report 36,776 magnitudes throughout its 67 day eruption, for an average of one measure every 2.6 minutes. This unique and unprecedented coverage is the first time that a nova has any substantial amount of fast photometry. With this, two new phenomena have been discovered: the fast flares in the early light curve seen from days 9-15 (which have no proposed explanation) and the optical dips seen out of eclipse from days 41-61 (likely caused by raised rims of the accretion disk occulting the bright inner regions of the disk as seen over specific orbital phases). The expanding shell and wind cleared enough from days 12-15 so that the inner binary system became visible, resulting in the sudden onset of eclipses and the turn-on of the supersoft X-ray source. On day 15, a strong asymmetry in the out-of-eclipse light points to the existence of the accretion stream. The normal optical flickering restarts on day 24.5. For days 15-26, eclipse mapping shows that the optical source is spherically symmetric with a radius of 4.1 R_sun. For days 26-41, the optical light is coming from a rim-bright disk of radius 3.4 R_sun. For days 41-67, the optical source is a center-bright disk of radius 2.2 R_sun. Throughout the eruption, the colors remain essentially constant. We present 12 eclipse times during eruption plus five just after the eruption.}, note = {arXiv: 1108.1214}, keywords = {}, pubstate = {published}, tppubtype = {article} } The eruption of the recurrent nova U Scorpii on 28 January 2010 is now the all-time best observed nova event. We report 36,776 magnitudes throughout its 67 day eruption, for an average of one measure every 2.6 minutes. This unique and unprecedented coverage is the first time that a nova has any substantial amount of fast photometry. With this, two new phenomena have been discovered: the fast flares in the early light curve seen from days 9-15 (which have no proposed explanation) and the optical dips seen out of eclipse from days 41-61 (likely caused by raised rims of the accretion disk occulting the bright inner regions of the disk as seen over specific orbital phases). The expanding shell and wind cleared enough from days 12-15 so that the inner binary system became visible, resulting in the sudden onset of eclipses and the turn-on of the supersoft X-ray source. On day 15, a strong asymmetry in the out-of-eclipse light points to the existence of the accretion stream. The normal optical flickering restarts on day 24.5. For days 15-26, eclipse mapping shows that the optical source is spherically symmetric with a radius of 4.1 R_sun. For days 26-41, the optical light is coming from a rim-bright disk of radius 3.4 R_sun. For days 41-67, the optical source is a center-bright disk of radius 2.2 R_sun. Throughout the eruption, the colors remain essentially constant. We present 12 eclipse times during eruption plus five just after the eruption. |
2009 |
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| 3. | Tan, T. G., Jacques, C., Pimentel, E. Supernova 2009gg in Pgc 65919 Journal Article Central Bureau Electronic Telegrams, 1848 , pp. 1, 2009. @article{tan_supernova_2009, title = {Supernova 2009gg in Pgc 65919}, author = {Tan, T. G. and Jacques, C. and Pimentel, E.}, url = {http://adsabs.harvard.edu/abs/2009CBET.1848....1T}, year = {2009}, date = {2009-01-01}, urldate = {2016-12-24}, journal = {Central Bureau Electronic Telegrams}, volume = {1848}, pages = {1}, abstract = {CBET 1848 available at Central Bureau for Astronomical Telegrams.}, keywords = {}, pubstate = {published}, tppubtype = {article} } CBET 1848 available at Central Bureau for Astronomical Telegrams. |
2008 |
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| 2. | Tan, T. G. Supernova 2008ff in Pgc 64319 Journal Article Central Bureau Electronic Telegrams, 1488 , pp. 1, 2008. @article{tan_supernova_2008, title = {Supernova 2008ff in Pgc 64319}, author = {Tan, T. G.}, url = {http://adsabs.harvard.edu/abs/2008CBET.1488....1T}, year = {2008}, date = {2008-09-01}, urldate = {2016-12-24}, journal = {Central Bureau Electronic Telegrams}, volume = {1488}, pages = {1}, abstract = {CBET 1488 available at Central Bureau for Astronomical Telegrams.}, keywords = {}, pubstate = {published}, tppubtype = {article} } CBET 1488 available at Central Bureau for Astronomical Telegrams. |
2007 |
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| 1. | Tan, T. G., Suzuki, M., Nakano, S., Nishiyama, K., Kabashima, F. Supernova 2007rv in NGC 689 Journal Article Central Bureau Electronic Telegrams, 1152 , pp. 1, 2007. @article{tan_supernova_2007, title = {Supernova 2007rv in NGC 689}, author = {Tan, T. G. and Suzuki, M. and Nakano, S. and Nishiyama, K. and Kabashima, F.}, url = {http://adsabs.harvard.edu/abs/2007CBET.1152....1T}, year = {2007}, date = {2007-12-01}, urldate = {2016-12-24}, journal = {Central Bureau Electronic Telegrams}, volume = {1152}, pages = {1}, abstract = {CBET 1152 available at Central Bureau for Astronomical Telegrams.}, keywords = {}, pubstate = {published}, tppubtype = {article} } CBET 1152 available at Central Bureau for Astronomical Telegrams. |