论文标题
原始星系的特性
Properties of Primitive Galaxies
论文作者
论文摘要
我们报告了一项对Hubble的COS Far-UV光谱仪观察到的附近9个恒星形成的，非常低的金属性星系，可以用作JWST观察到的高Z星系模板。我们发现，这些原始星系的螺旋光谱显示出X射线发射器辐射的证据。跟随Thuan等。 （2004年），我们将X射线发射的来源确定为包含巨大积聚恒星黑洞的巨大X射线二进制。我们进一步发现，金属性越低，强X辐射的概率越高。遵循Heger等。 （2003年），我们建议这些积聚的黑洞是由最初质量大于$ \ sim50 \，m_ \ odot $的恒星的直接崩溃而产生的。我们具有嵌入式恒星黑洞的年轻恒星簇模型在周围的气态介质上与观察到的光谱一致。我们得出的结论是，原始星系在质量上与富含金属的星系在质量上有所不同，这表明了硬辐射的证据，可以通过存在一个或多个嵌入式恒星黑洞来最好地解释。
We report on a study of 9 nearby star-forming, very low-metallicity galaxies observed by Hubble's COS far-UV spectrograph that can serve as templates of high-z galaxies to be observed by JWST. We find that the nebular spectra of these primitive galaxies show evidence of irradiation by X-ray emitters. Following Thuan et al. (2004), we identify the sources of X-ray emission as massive X-ray binaries containing a massive accreting stellar black hole. We further find that the lower the metallicity, the higher the probability of strong X-irradiation. Following Heger et al. (2003), we suggest that these accreting black holes are produced by direct collapse of stars having initial masses greater than $\sim50\, M_\odot$. Our models of young star clusters with an embedded stellar black hole produce effects on the surrounding gaseous medium that are consistent with the observed spectra. We conclude that primitive galaxies are qualitatively different from more metal-rich galaxies in showing evidence of hard radiation that can best be explained by the presence of one or more embedded stellar black holes.
