论文标题
用宇宙射线正电子分数来限制银河系的脉冲星人群
Constraining the Milky Way's Pulsar Population with the Cosmic-Ray Positron Fraction
论文作者
论文摘要
对与附近脉冲星相关的TEV光晕的观察表明，这些物体在星际培养基（ISM）中注入了非常高能量的电子质子的显着通量（ISM），从而可能为宇宙射线正电子通量提供了主导的贡献。在本文中，我们使用由AMS-02协作衡量的宇宙射线正电子分数来限制局部脉冲星人群的特征。对于合理的模型参数，我们发现我们可以与测量的正电子分数达到良好的一致性，直到$ e_e \ sim 300 \，{\ rm gev} $的能量。在较高的能量下，正电子馏分由少量脉冲星主导，因此很难可靠地预测预期的正电子分数的形状。低能量的正电子光谱支持以下结论：脉冲星通常将其总纺丝的总质量转移到大约$η\ sim 5-20 \％$中，以生产非常高的电子电子质子质子对生产，从而产生了具有硬频谱指数的一系列此类颗粒，这些粒子具有硬光谱指数，$α\ sim 1.5-1.5-1.5-1.7 $ $。这样的脉冲星通常在$τ\ sim 10^4 \，{\ rm年} $的订单上的时间表上旋转。对于模型，我们获得了我们最好的拟合，其中可以检测到来自脉冲星的无线电和伽马射线梁，分别可检测到周围观察者的28％和62％。
Observations of the TeV halos associated with nearby pulsars indicate that these objects inject significant fluxes of very high-energy electron-positrons pairs into the interstellar medium (ISM), thereby likely providing the dominant contribution to the cosmic-ray positron flux. In this paper, we use the cosmic-ray positron fraction as measured by the AMS-02 Collaboration to constrain the characteristics of the local pulsar population. For reasonable model parameters, we find that we can obtain good agreement with the measured positron fraction up to energies of $E_e \sim 300 \, {\rm GeV}$. At higher energies, the positron fraction is dominated by a small number of pulsars, making it difficult to reliably predict the shape of the expected positron fraction. The low-energy positron spectrum supports the conclusion that pulsars typically transfer approximately $η\sim 5-20\%$ of their total spindown power into the production of very high-energy electron-positron pairs, producing a spectrum of such particles with a hard spectral index, $α\sim 1.5-1.7$. Such pulsars typically spindown on a timescale on the order of $τ\sim 10^4 \, {\rm years}$. Our best fits were obtained for models in which the radio and gamma-ray beams from pulsars are detectable to 28% and 62% of surrounding observers, respectively.
