In this paper, we discuss the results of a new particle pusher in realistic ultra-strong electromagnetic fields such as those encountered around rotating neutron stars. After presenting the results of this algorithm in simple fields and comparing them to expected exact analytical solutions, we present new simulations for a rotating magnetic dipole in vacuum for a millisecond pulsar by using the Deutsch solution. Particles are injected within the magnetosphere, neglecting radiation reaction, interaction among them and their feedback on the fields. Our simulations are therefore not yet fully self-consistent because the Maxwell equations are not solved according to the current produced by these particles. The code highlights the symmetrical behaviour of particles of opposite charge to mass ratio,$q/m$, with respect to the north and south hemispheres. The relativistic Lorentz factor$\gamma$of the accelerated particles is proportional to this ratio$q/m$: protons reach up to$\gamma _p \simeq 10^{10.7}$, whereas electrons reach up to$\gamma _e \simeq 10^{14}$. Our simulations show that particles could either be captured by the neutron star, trapped around it or ejected far from it, well outside the light cylinder. Actually, for a given charge to mass ratio, particles follow similar trajectories. These particle orbits show some depleted directions, especially at high magnetic inclination with respect to the rotation axis for positive charges and at low inclination for negative charges because of symmetry. Other directions are preferred and loaded with a high density of particles, some directions concentrating the highest or lowest acceleration efficiencies.

中文翻译：

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中子星超强电磁场中的粒子加速

在本文中，我们讨论了一种新的粒子推进器在现实的超强电磁场中的结果，例如在旋转中子星周围遇到的那些。在简单领域展示了该算法的结果并将其与预期的精确解析解进行比较之后，我们使用 Deutsch 解对毫秒脉冲星的真空中旋转磁偶极子进行了新的模拟。粒子被注入磁层，忽略辐射反应、它们之间的相互作用以及它们对场的反馈。因此，我们的模拟还不是完全自洽的，因为麦克斯韦方程没有根据这些粒子产生的电流来求解。该代码突出了具有相反电荷质量比的粒子的对称行为，$q/m$，相对于南北半球。相对论洛伦兹因子$\伽马$加速粒子的数量与这个比率成正比$q/m$: 质子达到$\gamma _p \simeq 10^{10.7}$，而电子达到$\gamma _e \simeq 10^{14}$. 我们的模拟表明，粒子要么被中子星捕获，要么被困在它周围，要么被抛离它很远，远在光柱之外。实际上，对于给定的荷质比，粒子遵循相似的轨迹。这些粒子轨道显示出一些耗尽的方向，特别是在正电荷相对于旋转轴的高磁倾角和由于对称性而在负电荷的低磁倾角下。其他方向是优选的并且负载有高密度的粒子，一些方向集中了最高或最低的加速效率。