FIRST OBSERVATIONAL SIGNATURE OF ROTATIONAL DECELERATION IN A MASSIVE, INTERMEDIATE-AGE STAR CLUSTER IN THE MAGELLANIC CLOUDS

	FIRST OBSERVATIONAL SIGNATURE OF ROTATIONAL DECELERATION IN A MASSIVE, INTERMEDIATE-AGE STAR CLUSTER IN THE MAGELLANIC CLOUDS
	Wu, Xiaohan 1,2,3; Li, Chengyuan 2,3,4,5,6; de Grijs, Richard 2,3,7; Deng, Licai4
刊名	ASTROPHYSICAL JOURNAL LETTERS
	2016-07-20
卷号	826 期号:1
关键词	galaxies: star clusters: individual (NGC 419) Hertzsprung-Russell and C-M diagrams Magellanic Clouds stars: rotation
英文摘要	While the extended main-sequence turnoffs (eMSTOs) found in almost all 1-2 Gyr old star clusters in the Magellanic Clouds are often explained by postulating extended star formation histories (SFHs), the tight subgiant branches (SGBs) seen in some clusters challenge this popular scenario. Puzzlingly, the SGB of the eMSTO cluster NGC 419 is significantly broader at bluer than at redder colors. We carefully assess and confirm the reality of this observational trend. If we would assume that the widths of the features in color magnitude space were entirely owing to a range in stellar ages, the SFHs of the eMSTO stars and the blue SGB region would be significantly more prolonged than that of the red part of the SGB. This cannot be explained by assuming an internal age spread. We show that rotational deceleration of a population of rapidly rotating stars, a currently hotly debated alternative scenario, naturally explains the observed trend along the SGB. Our analysis shows that a "converging" SGB could be produced if the cluster is mostly composed of rapidly rotating stars that slow down over time owing to the conservation of angular momentum during their evolutionary expansion from main-sequence turnoff stars to red giants.
WOS标题词	Science & Technology ; Physical Sciences
类目[WOS]	Astronomy & Astrophysics
研究领域[WOS]	Astronomy & Astrophysics
关键词[WOS]	MULTIPLE STELLAR POPULATIONS ; MAIN-SEQUENCE TURNOFFS ; SUB-GIANT BRANCH ; M-CIRCLE-DOT ; FORMATION HISTORY ; NGC 419 ; MODELS ; EVOLUTION ; SPREADS ; GRIDS
收录类别	SCI
语种	英语
WOS记录号	WOS:000380739300014
内容类型	期刊论文
源URL	[http://ir.bao.ac.cn/handle/114a11/6785]
专题	国家天文台_光学天文研究部
作者单位	1.Peking Univ, Sch Phys, Yi He Yuan Lu 5, Beijing 100871, Peoples R China 2.Peking Univ, Kavli Inst Astron & Astrophys, Yi He Yuan Lu 5, Beijing 100871, Peoples R China 3.Peking Univ, Dept Astron, Yi He Yuan Lu 5, Beijing 100871, Peoples R China 4.Chinese Acad Sci, Natl Astron Observ, Key Lab Opt Astron, 20A Datun Rd, Beijing 100012, Peoples R China 5.Macquarie Univ, Dept Phys & Astron, Sydney, NSW 2109, Australia 6.Chinese Acad Sci, Purple Mt Observ, Nanjing 210008, Jiangsu, Peoples R China 7.Int Space Sci Inst Beijing, 1 Nanertiao, Beijing 100190, Peoples R China
推荐引用方式 GB/T 7714	Wu, Xiaohan,Li, Chengyuan,de Grijs, Richard,et al. FIRST OBSERVATIONAL SIGNATURE OF ROTATIONAL DECELERATION IN A MASSIVE, INTERMEDIATE-AGE STAR CLUSTER IN THE MAGELLANIC CLOUDS[J]. ASTROPHYSICAL JOURNAL LETTERS,2016,826(1).
APA	Wu, Xiaohan,Li, Chengyuan,de Grijs, Richard,&Deng, Licai.(2016).FIRST OBSERVATIONAL SIGNATURE OF ROTATIONAL DECELERATION IN A MASSIVE, INTERMEDIATE-AGE STAR CLUSTER IN THE MAGELLANIC CLOUDS.ASTROPHYSICAL JOURNAL LETTERS,826(1).
MLA	Wu, Xiaohan,et al."FIRST OBSERVATIONAL SIGNATURE OF ROTATIONAL DECELERATION IN A MASSIVE, INTERMEDIATE-AGE STAR CLUSTER IN THE MAGELLANIC CLOUDS".ASTROPHYSICAL JOURNAL LETTERS 826.1(2016).