论文标题
在4FGL目录银河平面源中搜索新的宇宙射线加速位点
Search for new cosmic-ray acceleration sites within the 4FGL catalog Galactic plane sources
论文作者
论文摘要
宇宙射线主要由加速到相对论速度的质子组成。当这些质子遇到星际材料时,它们会产生中性乳头,进而将其腐烂成伽玛射线。这提供了一种令人信服的方法来识别质子的加速位点。在四个超新星残留物(SNRS),IC 443,W44,W49B和W51C的伽马射线光谱中检测到了一个特征性的HADRONIC光谱,其特征性的频谱在200 MeV左右左右。该检测提供了直接的证据,表明宇宙射线质子在SNR中加速了(重新)。在这里,我们对311 4FGL目录源之间的低能光谱断裂进行了全面搜索,该频谱源位于距离银河平面5度以内。使用Fermi大面积望远镜的8年数据在50 MeV和1 GEV之间,我们发现并呈现了56个来源的光谱特征,并通过对系统不确定性进行了彻底的研究,并证实了光谱中断的光谱中断。我们的资料来源包括13个SNR,质子蛋白质相互作用通过致密靶材料增强。高质量伽马射线二进制LS〜I +61 303;碰撞的风二进制ETA CARINAE;和cygnus恒星形成区域。该分析更好地限制了伽马射线排放的起源,并将我们的观点扩大到潜在的新宇宙射线加速位点。
Cosmic rays are mostly composed of protons accelerated to relativistic speeds. When those protons encounter interstellar material, they produce neutral pions which in turn decay into gamma rays. This offers a compelling way to identify the acceleration sites of protons. A characteristic hadronic spectrum, with a low-energy break around 200 MeV, was detected in the gamma-ray spectra of four Supernova Remnants (SNRs), IC 443, W44, W49B and W51C, with the Fermi Large Area Telescope. This detection provided direct evidence that cosmic-ray protons are (re-)accelerated in SNRs. Here, we present a comprehensive search for low-energy spectral breaks among 311 4FGL catalog sources located within 5 degrees from the Galactic plane. Using 8 years of data from the Fermi Large Area Telescope between 50 MeV and 1 GeV, we find and present the spectral characteristics of 56 sources with a spectral break confirmed by a thorough study of systematic uncertainty. Our population of sources includes 13 SNRs for which the proton-proton interaction is enhanced by the dense target material; the high-mass gamma-ray binary LS~I +61 303; the colliding wind binary eta Carinae; and the Cygnus star-forming region. This analysis better constrains the origin of the gamma-ray emission and enlarges our view to potential new cosmic-ray acceleration sites.