论文标题
脚踝下方的大规模各向异性宇宙射线的各向异性
Large-scale anisotropies of extragalactic cosmic rays below the ankle
论文作者
论文摘要
我们研究了大角度尺度上的各向异性，这些尺度可能存在于宇宙射线的通量中，从层外源源到达地球，重点是第二膝盖和踝关节之间的能量范围。在这个能量范围内，颗粒受银河磁场的显着影响，然后在塑造预期各向异性方面起着相关的作用。银河磁场会偏转宇宙射线轨迹，从而修改了银河系光环之外存在的各向异性，尤其是与观察者的翻译运动相关的偶极性偶极性（Compton-Getting效应）。同样，由于银河系旋转，在地球观察者的参考框架中，银河场的电动成分在颗粒动量中产生较小的变化。这种加速度取决于宇宙射线的到达方向，因此在给定能量范围内观察到的通量中诱导各向异性。我们分析了通量的产生偶极成分的预期幅度和相位，并讨论了通过这些效应解释的可能性，右丝丝分布阶段的变化在1 EEV左右观察到。
We study the anisotropies on large angular scales which can be present in the flux of cosmic rays reaching the Earth from a population of extragalactic sources, focusing on the energy range between the second knee and the ankle. In this energy range the particles are significantly affected by the Galactic magnetic field, which then plays a relevant role in shaping the expected anisotropies. The Galactic magnetic field deflects the cosmic-ray trajectories and thus modifies the anisotropies present outside the halo of the Galaxy, in particular the dipolar one associated with the translational motion of the observer (Compton-Getting effect). Also, due to the Galactic rotation, in the reference frame of an observer at Earth there is an electric component of the Galactic field that produces a small change in the particles' momentum. This acceleration depends on the cosmic-ray arrival direction and it hence induces anisotropies in the flux observed in a given energy range. We analyse the expected amplitude and phase of the resulting dipolar component of the flux and discuss the possibility to explain via these effects the change in the phase of the right-ascension distribution which is observed at energies around 1 EeV.
