X射线消光的尘埃散射分量：对连续拟合和高分辨吸收边结构的影响
The dust scattering component of X-ray extinction: Effects on continuum fitting and high-resolution absorption edge structure
摘要：
对于任何具有亚弧分分辨率的X射线仪器（钱德拉，斯威夫特，XMM-牛顿）来说，尘埃颗粒的小角度散射对星际消光总量有重要贡献。然而，灰尘散射组件不包括在当前的吸收模型中：phabs，tbabs和tbnew。我们模拟了大量的钱德拉光谱，探索在光谱拟合和NH测量的偏差，而不包括消光尘埃散射。我们发现，如果不将灰尘散射，测量的NH将过大的基线水平的25%。这种效应是由望远镜的成像分辨率调制的，因为在用于提取点源信息的孔径内将捕获一些未分辨的散射光。在高分辨率光谱学中，尘埃散射显著增强了总消光光学深度和光电吸收边的形状。我们特别关注在0.7千电子伏的铁-L边缘，表明总消光模板很好地适合高分辨率光谱的三个X射线二进制文件从钱德拉存档：GX 9+9，XTE J1817-330，和天鹅座X-1。在尘埃是源固有的情况下，必须将基于尘埃材料的角范围的覆盖因子应用于消光曲线，而不管角成像分辨率如何。这种方法将特别适用于类星体吸收线系统中的尘埃，并可能限制活动星系核中的团块大小。
英文摘要：
Small angle scattering by dust grains causes a significant contribution to the total interstellar extinction for any X-ray instrument with sub-arcminute resolution (Chandra, Swift, XMM-Newton). However, the dust scattering component is not included in the current absorption models: phabs, tbabs, and tbnew. We simulate a large number of Chandra spectra to explore the bias in the spectral fit and NH measurements obtained without including extinction from dust scattering. We find that without incorporating dust scattering, the measured NH will be too large by a baseline level of 25%. This effect is modulated by the imaging resolution of the telescope, because some amount of unresolved scattered light will be captured within the aperture used to extract point source information. In high resolution spectroscopy, dust scattering significantly enhances the total extinction optical depth and the shape of the photoelectric absorption edges. We focus in particular on the Fe-L edge at 0.7 keV, showing that the total extinction template fits well to the high resolution spectrum of three X-ray binaries from the Chandra archive: GX 9+9, XTE J1817-330, and Cyg X-1. In cases where dust is intrinsic to the source, a covering factor based on the angular extent of the dusty material must be applied to the extinction curve, regardless of angular imaging resolution. This approach will be particularly relevant for dust in quasar absorption line systems and might constrain clump sizes in active galactic nuclei.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
