标题： 高I自旋温度在费米-LAT时代 显示英文标题

标题： H I spin temperature in the Fermi-LAT era

摘要： 银河系弥散的高能伽马射线辐射源于宇宙射线 (CRs) 与星系中的星际气体和辐射场之间的相互作用。 中性氢 (H I) 气体成分迄今为止是星际介质中最庞大且分布最广的成分。 利用原子氢的21厘米发射线从超精细结构跃迁中，如果已知发射气体的自旋温度 (Ts)，则可以确定H I 的柱密度。 弥散伽马射线发射的研究通常依赖于假设银河系中所有H I 的自旋温度固定且恒定。 不幸的是，对亮背景源吸收的H I 观测表明它在银河系中的位置变化很大。 我们将讨论使用费米伽马射线太空望远镜 (Fermi-LAT) 数据更好地处理银河系弥散发射的自旋温度的方法，以及通过H I 吸收直接观测自旋温度的方法。 显示英文摘要

摘要： The diffuse high-energy gamma-ray emission of the Milky Way arises from interactions of cosmic-rays (CRs) with interstellar gas and radiation field in the Galaxy. The neutral hydrogen (H I) gas component is by far the most massive and broadly distributed component of the interstellar medium. Using the 21-cm emission line from the hyperfine structure transition of atomic hydrogen it is possible to determine the column density of H I if the spin temperature (Ts) of the emitting gas is known. Studies of diffuse gamma-ray emission have generally relied on the assumption of a fixed, constant spin temperature for all H I in the Milky Way. Unfortunately, observations of H I in absorption against bright background sources has shown it to vary greatly with location in the Milky Way. We will discuss methods for better handling of spin temperatures for Galactic diffuse emission modeling using the Fermi-LAT data and direct observation of the spin temperature using H I absorption.