| タイトル | Ogle-2012-blg-0724lb: A Saturn Mass Planet Around an M-dwarf |
| 著者（英） | Bhattacharya, A.; Asakura, Y.; Hirao, Y.; Suzuki, D.; Sumi, T.; Bond, I. A.; Koshimoto, N.; Bennett, D. P.; Abe, F.; Rattenbury, N. |
| 著者所属（英） | NASA Goddard Space Flight Center |
| 発行日 | 2016-06-21 |
| 言語 | eng |
| 内容記述 | We report the discovery of a planet by the microlensing method, OGLE-2012-BLG-0724Lb. Although the duration of the planetary signal for this event was one of the shortest seen for a planetary event, the anomaly was well covered thanks to high-cadence observations taken by the survey groups OGLE and MOA. By analyzing the light curve, this planetary system is found to have a mass ratio q = (1.58 +/- 0.15) x 10(exp -3). By conducting a Bayesian analysis, we estimate that the host star is an M dwarf with a mass of M(sub L) = 0.29(+0.33/-0.16) solar mass located at D(sub L) = 6.7(+1.1/-1.2) kpc away from the Earth and the companion's mass is m(sub P) = 0.47(+0.54/-0.26) M(Jup). The projected planet- host separation is a falsum = 1.6(+0.4/-0.3) AU. Because the lens-source relative proper motion is relatively high, future highresolution images would detect the lens host star and determine the lens properties uniquely. This system is likely a Saturn-mass exoplanet around an M dwarf, and such systems are commonly detected by gravitational microlensing. This adds another example of a possible pileup of sub-Jupiters (0.2 less than m(sub P)/M(sub Jup) less than 1) in contrast to a lack of Jupiters (approximately 1-2 M(sub Jup)) around M dwarfs, supporting the prediction by core accretion models that Jupiter-mass or more massive planets are unlikely to form around M dwarfs. |
| NASA分類 | Astrophysics |
| レポートNO | GSFC-E-DAA-TN33865 |
| 権利 | Copyright |
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