论文标题
$γ$射线排放星系的排放
The $γ$-ray Emission of Star-Forming Galaxies
论文作者
论文摘要
高能宇宙射线与星际气体和辐射场的相互作用产生了来自星形星系的$γ$射线发射的大部分。预计星形的星系有助于造成阿加拉外$γ$ - 射线背景和Icecube天体中微子通量。使用{\ it fermi}大面积望远镜获取的$γ$ ray的年份大约10 \，在这项研究中，我们限制了星形星系的$γ$ ray属性。我们报告了11个真正的$γ$ ray排放星系和2个候选者的检测。此外，我们表明，在$ \ sim $ 5 \，$σ$ procurity的累积$γ$ -RARE排放率也被显着检测到。发现已分辨和未分辨星系的$γ$射线光度与以前确定的总（8-1000 \，$ $ m）红外发光度相关。在1 \，GEV上方，发现已解决和未解决的星系的光谱能分布与$ \ of $ \ of 2.2-2.3 $的光子指数的功率定律兼容。 最后，我们发现，恒星形成的星系大约是5 \，\％和3 \，\％的，分别分别为alagalactic $γ$ ray背景和iCecube Neutmonino通量。
A majority of the $γ$-ray emission from star-forming galaxies is generated by the interaction of high-energy cosmic rays with the interstellar gas and radiation fields. Star-forming galaxies are expected to contribute to both the extragalactic $γ$-ray background and the IceCube astrophysical neutrino flux. Using roughly 10\,years of $γ$-ray data taken by the {\it Fermi} Large Area Telescope, in this study we constrain the $γ$-ray properties of star-forming galaxies. We report the detection of 11 bona-fide $γ$-ray emitting galaxies and 2 candidates. Moreover, we show that the cumulative $γ$-ray emission of below-threshold galaxies is also significantly detected at $\sim$5\,$σ$ confidence. The $γ$-ray luminosity of resolved and unresolved galaxies is found to correlate with the total (8-1000\,$μ$m) infrared luminosity as previously determined. Above 1\,GeV, the spectral energy distribution of resolved and unresolved galaxies is found to be compatible with a power law with a photon index of $\approx2.2-2.3$. Finally, we find that star-forming galaxies account for roughly 5\,\% and 3\,\% of the extragalactic $γ$-ray background and the IceCube neutrino flux, respectively.
