The tight subgiant branch of the intermediate-age star cluster NGC 411 implies a single-aged stellar population

	The tight subgiant branch of the intermediate-age star cluster NGC 411 implies a single-aged stellar population
	Li, C.1,2,3,4,5 ; de Grijs, R.2,3,6; Bastian, N.7; Deng, L.4; Niederhofer, F.8,9,10; Zhang, C.11
刊名	MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
	2016-09-21
卷号	461 期号:3 页码:3212-3221
关键词	stars: rotation galaxies: clusters: individual: NGC 411
英文摘要	The presence of extended main-sequence turn-off (eMSTO) regions in intermediate-age star clusters in the Large and Small Magellanic Clouds is often interpreted as resulting from extended star formation histories (SFHs), lasting >= 300 Myr. This strongly conflicts with the traditional view of the dominant star formation mode in stellar clusters, which are thought of as single-aged stellar populations. Here we present a test of this interpretation by exploring the morphology of the subgiant branch (SGB) of NGC 411, which hosts possibly the most extended eMSTO among all known intermediate-age star clusters. We show that the width of the NGC 411 SGB favours the single-aged stellar population interpretation and rules out an extended SFH. In addition, when considering the red clump (RC) morphology and adopting the unproven premise that the widths of all features in the colour-magnitude diagram are determined by an underlying range in ages, we find that the SFH implied is still very close to that resulting from a single-aged stellar population, with a minor fraction of stars scattering to younger ages compared with the bulk of the population. The SFHs derived from the SGB and RC are both inconsistent with the SFH derived from the eMSTO region. NGC 411 has a very low escape velocity and it has unlikely undergone significant mass-loss at an early stage, thus indicating that it may lack the capacity to capture most of its initial, expelled gas from stellar evolutionary processes, a condition often required for extended SFHs to take root.
WOS标题词	Science & Technology ; Physical Sciences
类目[WOS]	Astronomy & Astrophysics
研究领域[WOS]	Astronomy & Astrophysics
关键词[WOS]	LARGE-MAGELLANIC-CLOUD ; SEQUENCE TURN-OFF ; YOUNG MASSIVE CLUSTERS ; SUB-GIANT BRANCH ; M-CIRCLE-DOT ; MAIN-SEQUENCE ; DYNAMICAL EVOLUTION ; GLOBULAR-CLUSTERS ; ESCAPE VELOCITY ; ROTATION
收录类别	SCI
语种	英语
WOS记录号	WOS:000383481100067
内容类型	期刊论文
源URL	[http://ir.bao.ac.cn/handle/114a11/6784]
专题	国家天文台_月球与深空探测研究部
作者单位	1.Chinese Acad Sci, Purple Mt Observ, Nanjing 210008, Jiangsu, 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, Key Lab Opt Astron, Natl Astron Observ, 20A Datun Rd, Beijing 100012, Peoples R China 5.Macquarie Univ, Dept Phys & Astron, Sydney, NSW 2109, Australia 6.Int Space Sci Inst Beijing, 1 Nanertiao, Beijing 100190, Peoples R China 7.Liverpool John Moores Univ, Astrophys Res Inst, 146 Brownlow Hill, Liverpool L3 5RF, Merseyside, England 8.Excellence Cluster Origin & Struct Universe, Boltzmannstr 2, D-85748 Garching, Germany 9.Univ Sternwarte Munchen, Scheinerstr 1, D-81679 Munich, Germany 10.Space Telescope Sci Inst, 3700 San Martin Dr, Baltimore, MD 21218 USA
推荐引用方式 GB/T 7714	Li, C.,de Grijs, R.,Bastian, N.,et al. The tight subgiant branch of the intermediate-age star cluster NGC 411 implies a single-aged stellar population[J]. MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY,2016,461(3):3212-3221.
APA	Li, C.,de Grijs, R.,Bastian, N.,Deng, L.,Niederhofer, F.,&Zhang, C..(2016).The tight subgiant branch of the intermediate-age star cluster NGC 411 implies a single-aged stellar population.MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY,461(3),3212-3221.
MLA	Li, C.,et al."The tight subgiant branch of the intermediate-age star cluster NGC 411 implies a single-aged stellar population".MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY 461.3(2016):3212-3221.