A hallowed part of the scientific method, papers are where discoveries are announced and described.
2013 |
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| 12. | 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. |
| 11. | 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. |
| 10. | 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. |
| 9. | 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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| 8. | 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. |
| 7. | 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. |
| 6. | 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. |
| 5. | 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. |
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. |