Exoplanet orbital eccentricities derived from LAMOST-Kepler analysis

	Exoplanet orbital eccentricities derived from LAMOST-Kepler analysis
	Xie, Ji-Wei 1,2; Dong, Subo 3; Zhu, Zhaohuan 4,5; Huber, Daniel 6,7,8; Zheng, Zheng9 ; De Cat, Peter 10; Fu, Jianning 11; Liu, Hui-Gen 1,2; Luo, Ali12 ; Wu, Yue12
刊名	PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
	2016-10-11
卷号	113 期号:41 页码:11431-11435
关键词	orbital eccentricities exoplanets transit solar system planetary dynamics
英文摘要	The nearly circular (mean eccentricity (e) over bar approximate to 0.06) and coplanar (mean mutual inclination (i) over bar approximate to 3 degrees) orbits of the solar system planets motivated Kant and Laplace to hypothesize that planets are formed in disks, which has developed into the widely accepted theory of planet formation. The first several hundred extrasolar planets (mostly Jovian) discovered using the radial velocity (RV) technique are commonly on eccentric orbits ((e) over bar approximate to 0.3). This raises a fundamental question: Are the solar system and its formation special? The Kepler mission has found thousands of transiting planets dominated by sub-Neptunes, but most of their orbital eccentricities remain unknown. By using the precise spectroscopic host star parameters from the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) observations, we measure the eccentricity distributions for a large (698) and homogeneous Kepler planet sample with transit duration statistics. Nearly half of the planets are in systems with single transiting planets (singles), whereas the other half are multiple transiting planets (multiples). We find an eccentricity dichotomy: on average, Kepler singles are on eccentric orbits with (e) over bar approximate to 0.3, whereas the multiples are on nearly circular ((e) over bar = 0.04(-0.04)(+0.03)) and coplanar ((i) over bar = 1.4(-1.1)(+0.8) degree) orbits similar to those of the solar system planets. Our results are consistent with previous studies of smaller samples and individual systems. We also show that Kepler multiples and solar system objects follow a common relation [(e) over bar approximate to (1-2) x (i) over bar] between mean eccentricities and mutual inclinations. The prevalence of circular orbits and the common relation may imply that the solar system is not so atypical in the galaxy after all.
WOS标题词	Science & Technology
类目[WOS]	Multidisciplinary Sciences
研究领域[WOS]	Science & Technology - Other Topics
关键词[WOS]	MULTI-PLANET SYSTEMS ; EXTRASOLAR PLANETS ; CANDIDATES ; PLANETESIMALS ; INSTABILITY ; DENSITIES ; DATABASE ; STARS
收录类别	SCI
语种	英语
WOS记录号	WOS:000384886900050
内容类型	期刊论文
源URL	[http://ir.bao.ac.cn/handle/114a11/6870]
专题	国家天文台_光学天文研究部
作者单位	1.Nanjing Univ, Sch Astron & Space Sci, Nanjing 210093, Jiangsu, Peoples R China 2.Nanjing Univ, Minist Educ, Key Lab Modern Astron & Astrophys, Nanjing 210093, Jiangsu, Peoples R China 3.Peking Univ, Kavli Inst Astron & Astrophys, Beijing 100871, Peoples R China 4.Princeton Univ, Dept Astrophys Sci, Princeton, NJ 08544 USA 5.Univ Nevada, Dept Phys & Astron, Las Vegas, NV 89154 USA 6.Univ Sydney, Sydney Inst Astron, Sch Phys, Sydney, NSW NSW2006, Australia 7.Search Extraterr Intelligence SETI Inst, Mountain View, CA 94043 USA 8.Aarhus Univ, Dept Phys & Astron, Stellar Astrophys Ctr, DK-8000 Aarhus C, Denmark 9.Univ Utah, Dept Phys & Astron, Salt Lake City, UT 84112 USA 10.Royal Observ Belgium, B-1180 Brussels, Belgium
推荐引用方式 GB/T 7714	Xie, Ji-Wei,Dong, Subo,Zhu, Zhaohuan,et al. Exoplanet orbital eccentricities derived from LAMOST-Kepler analysis[J]. PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA,2016,113(41):11431-11435.
APA	Xie, Ji-Wei.,Dong, Subo.,Zhu, Zhaohuan.,Huber, Daniel.,Zheng, Zheng.,...&Zhang, Yong.(2016).Exoplanet orbital eccentricities derived from LAMOST-Kepler analysis.PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA,113(41),11431-11435.
MLA	Xie, Ji-Wei,et al."Exoplanet orbital eccentricities derived from LAMOST-Kepler analysis".PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA 113.41(2016):11431-11435.