The Orbital Nature of 81 Ellipsoidal Red Giant Binaries in the Large Magellanic Cloud

	The Orbital Nature of 81 Ellipsoidal Red Giant Binaries in the Large Magellanic Cloud
	Nie, J. D.1; Wood, P. R.2; Nicholls, C. P.3
刊名	ASTROPHYSICAL JOURNAL
	2017-02-01
卷号	835 期号:2
关键词	binaries: close Magellanic Clouds stars: AGB and post-AGB
英文摘要	In this paper, we collect a sample of 81 ellipsoidal red giant binaries in the Large Magellanic Cloud (LMC), and we study their orbital natures individually and statistically. The sample contains 59 systems with circular orbits and 22 systems with eccentric orbits. We derive orbital solutions using the 2010 version of the Wilson-Devinney code. The sample is selection-bias corrected, and the orbital parameter distributions are compared to model predictions for the LMC and to observations in the solar vicinity. The masses of the red giant primaries are found to range from about 0.6 to 9 M-circle dot with a peak at around 1.5 M-circle dot, in agreement with studies of the star formation history of the LMC, which find a burst of star formation beginning around 4 Gyr ago. The observed distribution of mass ratios q= m(2)/m(1) is more consistent with the flat q distribution derived for the solar vicinity by Raghavan et al. than it is with the solar vicinity q distribution derived by Duquennoy & Mayor. There is no evidence for an excess number of systems with equal mass components. We find that about 20% of the ellipsoidal binaries have eccentric orbits, twice the fraction estimated by Soszynski et al. Our eccentricity evolution test shows that the existence of eccentric ellipsoidal red giant binaries on the upper parts of the red giant branch (RGB) can only be explained if tidal circularization rates are similar to 1/100 the rates given by the usual theory of tidal dissipation in convective stars.
WOS标题词	Science & Technology ; Physical Sciences
类目[WOS]	Astronomy & Astrophysics
研究领域[WOS]	Astronomy & Astrophysics
关键词[WOS]	GRAVITATIONAL LENSING EXPERIMENT ; PERIOD-LUMINOSITY RELATIONS ; COLOR-TEMPERATURE RELATIONS ; FIELD SPECTROGRAPH WIFES ; SOLAR-TYPE STARS ; VELOCITY CURVES ; TIDAL EVOLUTION ; VARIABLE-STARS ; POPULATIONS ; VARIABILITY
收录类别	SCI
语种	英语
WOS记录号	WOS:000401154800001
内容类型	期刊论文
源URL	[http://ir.bao.ac.cn/handle/114a11/8780]
专题	国家天文台_光学天文研究部
作者单位	1.Chinese Acad Sci, Key Lab Opt Astron, Natl Astron Observ, Beijing 100012, Peoples R China 2.Australian Natl Univ, Res Sch Astron & Astrophys, Canberra, ACT 2611, Australia 3.Univ Vienna, Inst Astrophys, Turkenschanzstr 17, A-1180 Vienna, Austria
推荐引用方式 GB/T 7714	Nie, J. D.,Wood, P. R.,Nicholls, C. P.. The Orbital Nature of 81 Ellipsoidal Red Giant Binaries in the Large Magellanic Cloud[J]. ASTROPHYSICAL JOURNAL,2017,835(2).
APA	Nie, J. D.,Wood, P. R.,&Nicholls, C. P..(2017).The Orbital Nature of 81 Ellipsoidal Red Giant Binaries in the Large Magellanic Cloud.ASTROPHYSICAL JOURNAL,835(2).
MLA	Nie, J. D.,et al."The Orbital Nature of 81 Ellipsoidal Red Giant Binaries in the Large Magellanic Cloud".ASTROPHYSICAL JOURNAL 835.2(2017).