论文标题
2008年3月9日在立体声冲击处加速粒子的双向流
Bi-directional streaming of particles accelerated at the STEREO-A shock on 9th March 2008
论文作者
论文摘要
我们介绍了在2008年3月9日通过太阳陆地关系天文台（ST-A）测量的快速准垂直反向冲击的各向异性和强度的解释。在冲击到达时，超细性颗粒的测得的强度曲线表现出增强或“尖峰”，并且在冲击到达前的倾斜角度各向异性表现出双模式，这是双模式的，表明在两个位置相交的磁场线沿着磁场线捕获了近距离无射线的离子。我们运行测试粒子仿真，并在冲击过程中进行预先存在的上游磁静电波动。测得的双模式上游各向异性，电击的上游近约15分钟的几乎田间对准的各向异性，以及在冲击的下游〜10分钟的“薄煎饼状”各向异性。这些结果与较早的作品一致，表明磁场的大规模结构（100s thermal质子质子gyroradii）在冲击时锻造早期粒子加速度方面具有主要作用。
We present an interpretation of anisotropy and intensity of supra-thermal ions near a fast quasi-perpendicular reverse shock measured by Solar Terrestrial Relations Observatory Ahead (ST-A) on 2008 March 9th. The measured intensity profiles of the supra-thermal particles exhibit an enhancement, or "spike", at the time of the shock arrival and pitch-angle anisotropies before the shock arrival are bi-modal, jointly suggesting trapping of near-scatter-free ions along magnetic field lines that intersect the shock at two locations. We run test-particle simulations with pre-existing upstream magnetostatic fluctuations advected across the shock. The measured bi-modal upstream anisotropy, the nearly field-aligned anisotropies up to ~15 minutes upstream of the shock, as well as the "pancake-like" anisotropies up to ~10 minutes downstream of the shock are well reproduced by the simulations. These results, in agreement with earlier works, suggest a dominant role of the large-scale structure (100s of supra-thermal proton gyroradii) of the magnetic field in forging the early-on particle acceleration at shocks.
