标题： 星系团的内部吸收 显示英文标题

标题： On the Internal Absorption of Galaxy Clusters

摘要： 使用爱因斯坦卫星的固体状态谱仪（SSS）对星系团核心的研究表明存在吸收物质，相当于冷星系团气体的质量为 1E+12 倍太阳质量，这可能是冷却流的结果。 由于这种冷气体的数量并未被其他波长的观测所证实，我们检查了在 20 个亮星系团的 ROSAT PSPC 观测数据中是否存在过量吸收。 对于 3/4 的星系团，仅银河系引起的吸收就得到了成功的光谱拟合，因此不需要在星系团内部存在额外的吸收，这与某些相同星系团的爱因斯坦 SSS 数据的结果不符。 对于 1/4 的星系团，我们的光谱拟合均不理想，表明比这里考虑的双温模型和冷却流模型更为复杂的星系团介质。 然而，即使对于这些星系团，也未显示出显著的过量吸收。 显示英文摘要

摘要： A study of the cores of galaxy clusters with the Einstein SSS indicated the presence of absorbing material corresponding to 1E+12 Msun of cold cluster gas, possibly resulting from cooling flows. Since this amount of cold gas is not confirmed by observations at other wavelengths, we examined whether this excess absorption is present in the ROSAT PSPC observations of 20 bright galaxy clusters. For 3/4 of the clusters, successful spectral fits were obtained with absorption due only to the Galaxy, and therefore no extra absorption is needed within the clusters, in disagreement with the results from the Einstein SSS data for some of the same clusters. For 1/4 of the clusters, none of our spectral fits was acceptable, suggesting a more complicated cluster medium than the two-temperature and cooling flow models considered here. However, even for these clusters, substantial excess absorption is not indicated.