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ヨネハラ アツノリ
YONEHARA ATSUNORI
米原 厚憲 所属 京都産業大学 理学部 宇宙物理・気象学科 職種 教授 |
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| 発行・発表の年月 | 2016/06 |
| 形態種別 | 研究論文 |
| 査読 | 査読あり |
| 標題 | OGLE-2012-BLG-0724Lb: A Saturn-mass Planet around an M-dwarf |
| 執筆形態 | その他 |
| 掲載誌名 | The Astrophysical Journal |
| 巻・号・頁 | 824(2),article id. 139頁 |
| 著者・共著者 | Y. Hirao,A. Udalski,T. Sumi,D. P. Bennett,I. A. Bond,N. Rattenbury,D. Suzuki,N. Koshimoto,F. Abe,Y. Asakura,A. Bhattacharya,M. Freeman,A. Fukui,Y. Itow,M. C. A. Li,C. H. Ling,K. Masuda,Y. Matsubara,T. Matsuo,Y. Muraki,M. Nagakane,K. Ohnishi,H. Oyokawa,To. Saito,A. Sharan,H. Shibai,D. J. Sullivan,P. J. Tristram,A. Yonehara,R. Poleski,J. Skowron,P. Mróz,M. K. Szymański,S. Kozłowski,P. Pietrukowicz,I. Soszyński,Ł. Wyzykowski,K. Ulaczyk |
| 概要 | We report the discovery of a planet by the microlensing method,<br />
OGLE-2012-BLG-0724Lb. Although the duration of the planetary signal for this<br /> event was one of the shortest seen for a planetary event, the anomaly was well<br /> covered thanks to high cadence observations taken by the survey groups OGLE and<br /> MOA. By analyzing the light curve, this planetary system is found to have a<br /> mass ratio $q=(1.58\pm0.15)\times10^{-3}$. By conducting a Bayesian analysis,<br /> we estimate that the host star is an M-dwarf star with a mass of $M_{\rm<br /> L}=0.29_{-0.16}^{+0.33} \ M_{\odot}$ located at $D_{\rm L}=6.7_{-1.2}^{+1.1} \<br /> {\rm kpc}$ away from the Earth and the companion's mass is $m_{\rm<br /> P}=0.47_{-0.26}^{+0.54} \ M_{\rm Jup}$. The projected planet-host separation is<br /> $a_{\perp}=1.6_{-0.3}^{+0.4} \ {\rm AU}$. Because the lens-source relative<br /> proper motion is relatively high, future high resolution images would detect<br /> the lens host star and determine the lens properties uniquely. This system is<br /> likely a Saturn-mass exoplanet around an M-dwarf and such systems are commonly<br /> detected by gravitational microlensing. This adds an another example of a<br /> possible pileup of sub-Jupiters $(0.2 < m_{\rm P}/M_{\rm Jup} < 1)$ in contrast<br /> to a lack of Jupiters ($\sim 1 - 2 \ M_{\rm Jup}$) around M-dwarfs, supporting<br /> the prediction by core accretion models that Jupiter-mass or more massive<br /> planets are unlikely to form around M-dwarfs. |
| DOI | 10.3847/0004-637X/824/2/139 |
| arXiv ID | arXiv:1604.05463 |
| PermalinkURL | http://arxiv.org/abs/1604.05463v1 |