中国科学院新疆天文台机构知识库

对宇宙线起源问题的探讨,正随着新一代地基和空间伽玛射线望远镜观测的开展而深化.作为普遍认为的能量在"膝"部以下宇宙线粒子主要加速场所的超新星遗迹,在Ge V–Te V能段探测到的样本在不断扩大,一些具有指示性意义的在流量、能谱方面的统计特征也得到显现.为证实作为宇宙线主体的相对论性质子能够由超新星遗迹的激波加速产生,对超新星遗迹的伽玛射线辐射的观测和理论研究,特别对于与分子云作用的超新星遗迹的强子作用伽玛射线辐射的研究,已取得较大的进展,其中W44,IC 443等遗迹在70 Me V附近?0介子衰变的特征性鼓包特别引人瞩目.对强子作用的辐射机制目前已可分为质子就地直接打击和逃逸扩散"照亮"分子云两大类.但对大样本超新星遗迹的伽玛射线辐射更系统的研究,包括对超新星遗迹的伽玛射线及多波段辐射谱进行合理模型计算、澄清这些遗迹所在星际环境中分子气体的分布情况,甚至基本地判明一些遗迹伽玛射线辐射轻强子作用属性等,都还有大量工作要做.本文将概述近年在以上相关各方面研究的进展情况.

With the observations of the ground-based and space -ray telescopes, the study on the origin of cosmic rays (CRs) has been deepened. As sources of CRs below the “knee” energy, the sample of supernova remnants (SNRs) with GeV–TeV γ-ray emission is being enlarged, getting to show some statistical properties in flux, spectra, etc. Appreciable observational and theoretical efforts have been made to investigate the radiation mechanisms of the γ-ray emission from SNRs and, especially, the hadronic interaction between SNRs and molecular clouds (MCs) so as to verify the scenario that relativistic protons, as the main component of CRs, can be produced by the SNR shocks. The detection of characteristic π0-decay bump at 70 MeV in SNRs W44 and IC 443 marks a great progress in this regard. There are essentially two types of models explaining the hadronic γ-ray emission: direct proton-MC collision at the SNR shocks and MC “illumination” by escaped protons. A lot of work still need to do, such as systematic researches with a larger sample of -ray emitting SNRs, reasonable model calculation of the SNR emission in γ-rays together with other wavelengths, investigation of the molecular environment of SNRs, and even basic distinguishing of hardronic/leptonic property of the γ-ray emission. In this article, we will briefly summarize the present status of the above-mentioned studies.