Detection of Wolf-Rayet stars of WN and WC subtypes in superstar clusters of NGC 5253

被引:54
作者
Schaerer, D
Contini, T
Kunth, D
Meynet, G
机构
[1] OBSERV GENEVA,CH-1290 SAUVERNY,SWITZERLAND
[2] OBSERV MIDI PYRENEES,UMR 5572,F-31400 TOULOUSE,FRANCE
[3] TEL AVIV UNIV,SCH PHYS & ASTRON,IL-69978 TEL AVIV,ISRAEL
[4] INST ASTROPHYS,CNRS,F-75014 PARIS,FRANCE
关键词
galaxies; individual; (NGC; 5253); ISM; starburst; H II regions; stars; Wolf-Rayet;
D O I
10.1086/310659
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
We present spectroscopic observations of the central star clusters in NGC 5253, the aim of which is to search for WC stars. Our observations show the presence of Wolf-Rayet (W-R) stars not only of WN but also of WC subtype in two star-forming regions corresponding to the maximum optical and UV emission. The massive star population that we derive is consistent with young bursts of similar to 3 and similar to 4 Myr. The region of maximum optical emission is found to provide the dominant contribution to the ionizing flux, as opposed to the less extinguished region of maximum UV brightness. The presence of W-R stars near the N-enriched regions found by Walsh & Roy and Kobulnicky et al. suggests that they are a possible source of nitrogen. It is presently unclear whether our detection of WC stars is compatible with the normal observed He/O and C/O abundance ratios.
引用
收藏
页码:L75 / L79
页数:5
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