Binary Stars as the Source of the Far-UV Excess in Elliptical Galaxies

	Binary Stars as the Source of the Far-UV Excess in Elliptical Galaxies
	Han ZW(韩占文); Podsiadlowski, P; Lynas-Gray, AE; Han ZW(韩占文)
	2009
会议名称	International Conference on Untraviolet Properties of Evolved Stellar Populations
会议日期	2007-04-16
会议地点	Puerto Vallarta, MEXICO
页码	59-65
通讯作者	Han, ZW (reprint author), Chinese Acad Sci, Natl Astron Observ, Yunnan Observ, Kunming 650011, Peoples R China.
英文摘要	The discovery of an excess of light in the far-ultraviolet (UV) spectrum in elliptical galaxies was a major surprise in 1969. While it is now clear that this UV excess is caused by an old population of hot helium-burning stars without large hydrogen-rich envelopes rather than young stars, their origin has remained a mystery. Here we show that these stars most likely lost their envelopes because of binary interactions, similar to the hot subdwarf population in our own Galaxy. This has major implications for understanding the evolution of the UV excess and of elliptical galaxies in general. In particular, it implies that the UV excess is not a sign of age, as had been postulated previously, and predicts that it should not be strongly dependent on the metallicity of the population.
收录类别	CPCI
产权排序	第一完成单位
会议网址	http://link.springer.com/chapter/10.1007%2F978-0-387-87621-4_8
会议录	Astrophysics and Space Science Proceedings - NEW QUESTS IN STELLAR ASTROPHYSICS II
会议录出版者	SPRINGER
会议录出版地	233 SPRING STREET, NEW YORK, NY 10013, UNITED STATES
学科主题	Astronomy & Astrophysics
语种	英语
ISSN号	1570-6591
ISBN号	978-0-387-87620-7
内容类型	会议论文
源URL	[http://ir.ynao.ac.cn/handle/114a53/245]
专题	云南天文台_大样本恒星演化研究组
通讯作者	Han ZW(韩占文)
推荐引用方式 GB/T 7714	Han ZW,Podsiadlowski, P,Lynas-Gray, AE,et al. Binary Stars as the Source of the Far-UV Excess in Elliptical Galaxies[C]. 见:International Conference on Untraviolet Properties of Evolved Stellar Populations. Puerto Vallarta, MEXICO. 2007-04-16.http://link.springer.com/chapter/10.1007%2F978-0-387-87621-4_8.