论文标题
银河系磁场偏见对UHECR数据的推论
Galactic Magnetic Field Bias on Inferences from UHECR Data
论文作者
论文摘要
liouville定理的结果表明，最近观察到的大规模各向异性在超高能量宇宙射线（UHECR）的到达方向上不能由银河磁场产生，因此这种各向异性已经需要在我们的星系外面存在。但是在这种情况下，由于抑制或通过银河系磁场从某些方向对UHECR通量的抑制或扩增，观察到的UHECR的能量光谱和UHECR的组成与银河系的外部有所不同。在这项工作中，我们研究了偶极子和四极各向异性的情况，分别为广泛使用的JF12磁场模型进行了研究。我们研究了观察到的各向异性的最大振幅和UHECR的最大电荷数。此外，根据有关最近的偶极子以及化学成分的螺旋数据的数据，讨论了通量的修饰。我们发现，这种修饰效果对所研究的磁场模型和观察到的偶极子的观察到的通量最高为$ \ sim 10 \％$，特别是对于“ EPOS-LHC”模型建议的UHECRS的重型化学成分。
A consequence of Liouville's theorem indicates that the recently observed large scale anisotropy in the arrival direction of Ultra-High-Energy Cosmic Rays (UHECRs) cannot be produced by the Galactic magnetic field, thus this anisotropy already needs to be present outside our Galaxy. But in this case, the observed energy spectrum and composition of UHECRs differs from the one outside of the Milky Way, due to the suppression or the amplification of the UHECR flux from certain directions by the Galactic magnetic field. In this work, we investigate this effect for the case of a dipole and a quadrupole anisotropy, respectively, for the widely-used JF12 magnetic field model. We investigate boundaries on the maximal amplitude of the observed anisotropy and the maximal charge number of UHECRs. Furthermore, the flux modification is discussed in the light of the Auger data on the recent dipole and also the chemical composition. We find that this modification effect yields a modification of the observed flux of up to $\sim 10\%$ for the investigated magnetic field model and the observed dipole, in particular for a heavy chemical composition of UHECRs as suggested by the 'EPOS-LHC' model.
