标题： BeppoSAX对邻近星暴星系NGC 253中Fe K线的探测 显示英文标题

标题： BeppoSAX detection of the Fe K line in the nearby starburst galaxy NGC 253

摘要： 我们展示了BeppoSAX对邻近星暴星系NGC 253的结果。 尽管发射范围较广，但大部分X射线辐射来自核区。 对中心4'区域的LECS/MECS/PDS ~0.2-60 keV数据的初步分析表明，连续谱可以通过两个热模型很好地拟合：一个“软”成分，kT ~ 0.9 keV，以及一个“硬”成分，kT ~ 6 keV，被柱密度为~ 1.2 x10**22 cm-2的物质吸收。 这是首次在该天体中检测到6.7 keV处的Fe K线，其等效宽度约为300 eV。 这一检测以及2--60 keV连续谱的形状表明，大部分硬X射线辐射是热起源的，并将该成分的铁丰度限制为约为太阳的0.25倍。 明显检测到的其他线条包括Si、S和Fe L/Ne，这与之前的ASCA结果一致。 我们将在星暴驱动的星系超风模型的背景下讨论我们的结果。 显示英文摘要

摘要： We present BeppoSAX results on the nearby starburst galaxy NGC 253. Although extended, a large fraction of the X-ray emission comes from the nuclear region. Preliminary analysis of the LECS/MECS/PDS ~0.2-60 keV data from the central 4' region indicates that the continuum is well fitted by two thermal models: a ``soft'' component with kT ~ 0.9 keV, and a ``hard'' component with kT ~ 6 keV absorbed by a column density of ~ 1.2 x10**22 cm-2. For the first time in this object, the Fe K line at 6.7 keV is detected, with an equivalent width of ~ 300 eV. This detection, together with the shape of the 2--60 keV continuum, implies that most of the hard X-ray emission is thermal in origin, and constrains the iron abundances of this component to be ~0.25 of solar. Other lines clearly detected are Si, S and Fe L/Ne, in agreement with previous ASCA results. We discuss our results in the context of the starburst-driven galactic superwind model.