论文标题
外层次伽马射线助力的幂律形式的起源
The origin of the power-law form of the extragalactic gamma-ray flux
论文作者
论文摘要
费米 - 拉特望远镜已经测量了由所有外层次源的合奏产生的乳突外伽玛射线背景（EGB）。 EGB的能量分布被很好地描述为具有频谱指数大约等于2.3的幂律，并且指数截止值是一致的，这与吸收高能光子的效果，假设发射是不间断的幂律光谱。费米望远镜的观察结果也解决了EGB，确定其中大多数是由Blazar类活动的Active Galactic Nuclei（AGN）的贡献之和形成的。单个AGN源的光谱具有广泛的光谱形状，并且最亮，最精确的源具有弯曲光谱，可以与“ log-parabola”（或log-nortoral）形式拟合。具有不同光谱形状的贡献总和会产生具有简单幂律形式的光谱，这似乎令人惊讶。我们建议这一事实揭示了外乳外源集合的一些重要特性，并表明Blazar高能发射可以被视为“关键现象”。还需要一个弯曲的对数 - 果皮（对数正态）形式来适应许多银河系γ射线源的光谱，包括最明亮的超新星残留物（SNR）的排放，并且很有可能是，很有趣的可能性在于，同样在范围内将众所周知的范围内的范围内的范围内的范围内的范围内的范围注射，而不是单次通用的范围，而不是单次通用范围，而不是单一的普遍性范围，但范围是单一范围的范围。光谱形状。
The Fermi-LAT telescope has measured the extragalactic gamma-ray background (EGB) generated by the ensemble of all extragalactic sources. The energy distribution of the EGB is well described as a power-law with a spectral index approximately equal to 2.3, and an exponential cutoff, that is consistent with being the effect of absorption of high energy photons assuming an emission that is an unbroken power-law spectrum. The observations of the Fermi telescope have also resolved the EGB, determining that most of it is formed by the sum of the contributions of Active Galactic Nuclei (AGN) of the blazar class. The spectra of the individual AGN sources have a broad range of spectral shapes, and the brightest and most precisely measured sources have curved spectra that can be fitted with the "log-parabola" (or log-normal) form. It might appear surprising that the sum of contributions with different spectral shapes generate a spectrum that has a simple power-law form. We suggest that this fact reveals some important properties for the ensemble of the extragalactic sources, and indicates that the blazar high energy emission can be considered as a "critical phenomenon". A curved log--parabola (log-normal) form is also required to fit the spectra of many Galactic gamma-ray sources, including the emission from the brightest supernova remnants (SNR), and an intriguing possibility is that also the Galactic cosmic rays are injected in interstellar space by their sources not with a single universal power-law spectrum, as predicted by the commonly accepted models, but instead with a broad range of spectral shapes.
