标题： 窄线赛弗特1型星系中的温吸收体 显示英文标题

标题： Warm absorbers in Narrow-Line Seyfert 1 galaxies

摘要： 温吸收体是研究活动星系核中心区域条件的一种重要新工具，已在约50%的 Seyfert 星系以及许多窄线 Seyfert 1 星系（NLSy1）中被观测到。本文研究了几个 NLSy1 的 X 射线性质，重点关注它们的温吸收体：(a) 对所有 ROSAT PSPC 观测 NGC 4051 的数据（包括新的观测数据）进行了分析，发现计数率变化了大约 30 倍，而温吸收体参数的变化则小得多。(b) 基于尘埃温气体的光离化模型和明确的 ROSAT 光谱拟合，探讨了 IRAS 13349+2438 中可能存在尘埃温吸收体的可能性。(c) 分析了 NLSy1 1E0117.2-2837 的 X 射线谱，可以用非常陡峭的光子指数为 G_x = -4 的幂律很好地描述，或者用被温吸收的平坦幂律来描述。预计会从温物质中产生 UV-EUV 发射线。(d) 通过温吸收的视角，研究了 RX J0134.3-4258 的强光谱变化（从 ROSAT 巡天观测中的 G_x = -4.4 到我们后续指向观测中的 ~ -2.2）。 显示英文摘要

摘要： Warm absorbers are an important new tool for investigating the conditions within the central regions of active galaxies. They have been observed in ~50% of the well-studied Seyfert galaxies and have also been detected in quite a number of Narrow-line Seyfert 1 galaxies (NLSy1). Here, we present a study of the X-ray properties of several NLSy1s with focus on their warm absorbers: (a) An analysis of all ROSAT PSPC observations of NGC 4051 including new ones is performed, which reveals variability by a factor ~30 in count rate and much less variability in the warm absorber parameters. (b) The possibility of a dusty warm absorber in IRAS 13349+2438 is explored on the basis of photoionization models for dusty warm gas and explicit ROSAT spectral fits. (c) The X-ray spectrum of the NLSy1 1E0117.2-2837 is analyzed. It can be successfully described by a very steep powerlaw of photon index G_x = -4, or alternatively by a warm-absorbed flat powerlaw. UV-EUV emission lines expected to arise from the warm material are predicted. (d) The strong spectral variability of RX J0134.3-4258 (from G_x = -4.4 in the ROSAT survey observation, to ~ -2.2$ in our subsequent pointing) is examined in terms of warm absorption.