Stellar Populations in the Phoenix Dwarf (dIrr/dSph) Galaxy as Observed by Hubble Space Telescope WFPC2
Stellar Populations in the Phoenix Dwarf (dIrr/dSph) Galaxy as Observed by Hubble Space Telescope WFPC2
复制标题
哈勃太空望远镜 WFPC2 观测到的凤凰矮星 (dIrr/dSph) 星系中的恒星群
DOI：
10.1086/316844
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发表时间：
2000
期刊：
影响因子：
--
通讯作者：
C. Grillmair
中科院分区：
文献类型：
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作者：
J. Holtzman;Graeme H. Smith;C. Grillmair
我们目前的哈勃空间望远镜宽视场行星相机2光度的凤凰矮星系的中心区域。精确的测光使我们能够（1）确认先前通过地面观测检测到的水平分支的存在，并利用它来确定到凤凰的距离，（2）清楚地检测到凤凰恒星群中存在多个年龄，（3）确定凤凰中古老红巨星分支恒星的平均金属丰度，并表明凤凰在其一生中经历了化学进化，以及（4）提取出中心区域的一个粗略的星星形成历史，这表明凤凰号在其整个生命周期中一直在不断地形成恒星。
We present Hubble Space Telescope Wide Field Planetary Camera 2 photometry of the central regions of the Phoenix dwarf galaxy. Accurate photometry allows us to (1) confirm the existence of the horizontal branch previously detected by ground-based observations and use it to determine a distance to Phoenix, (2) clearly detect the existence of multiple ages in the stellar population of Phoenix, (3) determine a mean metallicity of the old red giant branch stars in Phoenix and suggest that Phoenix has evolved chemically over its lifetime, and (4) extract a rough star formation history for the central regions, which suggests that Phoenix has been forming stars roughly continuously over its entire lifetime.