arXiv 1905.012392019-05astro-ph.EP

MOA-bin-29 b：一颗围绕低质量主星运行的微透镜气体巨行星

MOA-bin-29b : A Microlensing Gas Giant Planet Orbiting a Low-mass Host Star

Iona Kondo, Takahiro Sumi, David P. Bennett, Andrzej Udalski, Ian A. Bond, Nicholas J. Rattenbury, Valerio Bozza, Yuki Hirao, Daisuke Suzuki, Naoki Koshimoto, M… 展开作者

Iona Kondo, Takahiro Sumi, David P. Bennett, Andrzej Udalski, Ian A. Bond, Nicholas J. Rattenbury, Valerio Bozza, Yuki Hirao, Daisuke Suzuki, Naoki Koshimoto, Masayuki Nagakane, Shota Miyazaki, Fumio Abe, Richard Barry, Aparna Bhattacharya, Martin Donachie, Akihiko Fukui, Hirosane Fujii, Yoshitaka Itow, Yuhei Kamei, Man Cheung Alex Li, Yutaka Matsubara, Taro Matsuo, Yasushi Muraki, Clément Ranc, Hiroshi Shibai, Haruno Suematsu, Denis J. Sullivan, Paul J. Tristram, Takeharu Yamakawa, Atsunori Yonehara, Przemek Mróz, Michał K. Szymański, Igor Soszyński, Krzysztof Ulaczyk

备注：: 26 pages, 16 figures, 5 tables. Accepted for publication in AJ
DOI：: 10.3847/1538-3881/ab4e9e

阅读 PDF

arXiv 页面 ↗HTML 原文 ↗

摘要：

我们报告了在2006年发生的微透镜事件MOA-bin-29中发现了一颗围绕低质量宿主恒星运行的气体巨行星。我们发现了五个退化的解决方案与行星/主星质量比为$q \sim 10^{-2}$。所有模型的爱因斯坦半径穿越时间都比较短（$\sim 4-7$天），这表明宿主星的质量可能较低。测量的透镜-源自行为$5-9$ ${\rm mas}\ {\rm yr}^{-1}$，具体取决于型号。由于只有有限的源效应被检测到，我们进行贝叶斯分析，以获得后验概率分布的透镜的物理特性。因此，我们发现该透镜系统很可能是一颗围绕着银河系核球中的褐矮星或极晚期M矮星运行的气体巨星。在误差范围内，五种简并模型的物理参数的概率分布是一致的。通过结合这些概率分布，我们得出结论，该透镜系统是一个质量为$M_{\rm p} = 0.63^{+1.13}_{-0.39}\ M_{\rm Jup}$的气体巨星，它围绕着质量为$M_{\rm h} = 0.06^{+0.11}_{-0.04}\ M_\odot$的褐矮星旋转，预计恒星与行星之间的距离为$r_\perp = 0.53^{+0.89}_{-0.18}\ {\rm au}$。透镜距离为$D_{\rm L} = 6.89^{+1.19}_{-1.19}\ {\rm kpc}$，即，很可能在银河系的凸起处

英文摘要：

We report the discovery of a gas giant planet orbiting a low-mass host star in the microlensing event MOA-bin-29 that occurred in 2006. We find five degenerate solutions with the planet/host-star mass ratio of $q \sim 10^{-2}$. The Einstein radius crossing time of all models are relatively short ($\sim 4-7$ days), which indicates that the mass of host star is likely low. The measured lens-source proper motion is $5-9$ ${\rm mas}\ {\rm yr}^{-1}$ depending on the models. Since only finite source effects are detected, we conduct a Bayesian analysis in order to obtain the posterior probability distribution of the lens physical properties. As a result, we find the lens system is likely to be a gas giant orbiting a brown dwarf or a very late M-dwarf in the Galactic bulge. The probability distributions of the physical parameters for the five degenerate models are consistent within the range of error. By combining these probability distributions, we conclude that the lens system is a gas giant with a mass of $M_{\rm p} = 0.63^{+1.13}_{-0.39}\ M_{\rm Jup}$ orbiting a brown dwarf with a mass of $M_{\rm h} = 0.06^{+0.11}_{-0.04}\ M_\odot$ at a projected star-planet separation of $r_\perp = 0.53^{+0.89}_{-0.18}\ {\rm au}$. The lens distance is $D_{\rm L} = 6.89^{+1.19}_{-1.19}\ {\rm kpc}$, i.e., likely within the Galactic bulge.

机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。

摘要：

英文摘要：

相关论文