对银河系高能伽玛射线源的多能段研究

Fermi Gamma-Ray Space Telescope (Fermi) has revolutionized our view of the high energy sky. Thus far approximately three thousand　gamma-ray sources have been detected by Fermi. Among the detected, nearly one thousand cannot be found to be associated with any known objects. In this program, we propose to mainly study these unassociated sources at multiple energies. For the sources near the Galactic plane, we plan to identify the pulsars among them from Fermi data analysis and targeted radio observations, to search for gamma-ray counterparts to peculiar X-ray binaries, and to study gamma-ray emission from related pulsar wind nebulae or supernova　remnants. For the sources with high Galactic latitudes, we plan to identify the millisecond pulsar (MSP) binaries from Fermi data analysis and X-ray and optical observations. Recent studies, including ours, have indicated the presence of intrabinary gamma-ray emission due to the interaction between the pulsar wind and low-mass companion for eclipsing MSP binaries, and therefore we will also explore the general existence of intrabinary gamma-ray emission among any newly identified systems. Supported by this program, we will help obtain a more complete census of populations of the Fermi sources, study their high-energy physical processes and emission mechanisms, and thus better understand the origins of cosmic rays.

费米伽玛射线空间望远镜前所未有的观测能力使得约3千颗高能伽玛射线源被探测到，而其中约1千颗还未被认证。通过此项目支持，我们计划使用多能段观测手段研究其中的银河系源。对于银道面附近的源，我们将通过费米数据分析和射电观测重点认证年轻脉冲星、搜寻X射线双星可能的伽玛射线辐射、探索与脉冲星星风云和超新星遗迹相关联的伽玛射线辐射。对于高银纬的源，我们将通过费米数据分析、X射线和光学观测搜寻认证其中的毫秒脉冲星双星系统；最近包括我们的工作在内的研究表明，数颗具有星蚀现象的双星系统由于星风和伴星间的作用可产生伽玛射线辐射，所以对星蚀毫秒脉冲星双星际辐射的探索也将得到开展。我们的工作将帮助进一步区分伽玛射线源的类别，加深对各类源背后的物理过程和辐射机制的理解，同时达到更深入地探索宇宙射线起源这一天体物理基本问题的目标。

按研究计划，我们对银河系三类高能天体源开展了广泛深入的观测和理论研究，并根据具体研究进展将工作拓展到河外耀变体和伽马暴。我们系统地总结了脉冲星的高能特性，并有针对性地对几类脉冲星及脉冲星相关天体开展了工作，对理解脉冲星这类银河系主要高能源起到了一定作用。我们梳理了不同子类X射线双星的可能高能辐射机制并相应开展了工作，发现它们都可能有可探测的高能辐射，从而帮助构建了X双星的高能辐射过程。我们对超新星遗迹这类银河系高能粒子加速器开展了全面的研究，包括了它们高能粒子加速机制、高能辐射特性、遗迹的前身星和环境等方面，极大帮助提升了我们对超新星遗迹物理的理解。另外，我们对耀变体的准周期振荡进行了关键性的研究，工作表明了准周期振荡对星系中心超大质量黑洞系统物理过程的揭示作用。总结来说，通过此项目支持，我们全面完成了计划对银河系高能天体物理特性的研究。