论文标题
M31中Chandra X射线源的Astrosat紫外线检测
AstroSat UVIT Detections of Chandra X-ray Sources in M31
论文作者
论文摘要
2017 - 19年度，紫外线仪器在Astrosat天文台上进行了紫外线调查。在这里，我们将M31 UVIT源目录（Leahy等，2020）与Chandra源目录（Vulic等，2016）匹配。我们发现在不同数量的紫外线和X射线频带中检测到67个Uvit/Chandra源。使用PowerLaw和Blackbody模型分析UV和X射线光度法。 X射线类型包括15个LMXB和5个AGN。与恒星，簇和其他源类型的目录交叉匹配产生以下内容。 20个紫外线/钱德拉来源与M31球状簇相匹配，而前景则有9个。尽管在Chandra匹配半径1 Arcsec的半径之外，还有3个球状簇和2颗前景恒星与紫外线源位置一致。与球状簇相关的UVIT/Chandra源的紫外线发射与蓝色水平分支星星的发射一致，而不是X射线源。球状簇中的LMXB是M31的最明亮的球状簇之一。与恒星进化轨道相比，表明具有高紫外线黑体温度的紫外线/chandra源与M31中的紫外线高度高（10至30 m $ _ $ _ {\ odot} $）一致。
An ultraviolet survey of M31 has been carried out during 2017-19 with the UVIT instrument onboard the AstroSat Observatory. Here we match the M31 UVIT source catalog (Leahy et al. 2020) with the Chandra source catalog (Vulic et al. 2016). We find 67 UVIT/Chandra sources detected in a varying number of UV and X-ray bands. The UV and X-ray photometry is analyzed using powerlaw and blackbody models. The X-ray types include 15 LMXBs and 5 AGNs. Cross-matches with catalogs of stars, clusters and other source types yield the following. 20 of the UVIT/Chandra sources match with M31 globular clusters and 9 with foreground stars. 3 more globular clusters and 2 more foreground stars are consistent with the UVIT source positions although outside the Chandra match radius of 1 arcsec. The UV emission of the UVIT/Chandra sources associated with globular clusters is consistent with emission from blue horizontal branch stars rather than from the X-ray source. The LMXBs in globular clusters are among the most luminous globular clusters in M31.Comparison with stellar evolutionary tracks shows that the UVIT/Chandra sources with high UV blackbody temperatures are consistent with massive (10 to 30 M$_{\odot}$) stars in M31.
