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arXiv 1702.00732astro-ph.HE
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脉冲星磁层模拟的新进展

New Advances in Pulsar Magnetosphere Modelling

Christo Venter

摘要:

过去几年积累的大量高能(E > 50 MeV)和甚高能(E > 100 GeV)数据为探索脉冲星发射模型提供了前所未有的机会。费米大面积望远镜(LAT)现在已经探测到200多个年龄差异很大的伽马射线天体,与十年前相比,提供了广泛的光谱和光变曲线数据集。地面切伦科夫望远镜通过对蟹状星云脉冲星高达1 TeV的脉冲发射的意外探测,加深了我们对脉冲星机制神秘丰富性的理解。这些发现使我们能够在脉冲星理论方面取得真正的进展。许多研究开发了新的和增强现有的耗散磁流体动力学(MHD)和粒子在细胞(PIC)的代码来解决全球电动力学和追求磁层粒子注入,加速和辐射的基本问题。虽然MHD模型捕捉脉冲星磁层的全球方面,微观物理需要探索自洽PIC模拟。一些耗散的MHD模型认为电流片(CS)是高能曲率辐射(CR)的重要场所,而早期的PIC结果指出能量耗散发生在CS中,在CS中,粒子通过磁重联加速,并可能通过同步辐射(SR)发射$γ$射线。这与一些旧的局部辐射模型形成鲜明对比,这些模型研究了在更接近旋转的中子星的间隙中产生的CR伽马射线。这些结果的普遍性应变得更加清晰,目前的计算限制,克服和边界条件的细化。持续的和综合的偏振,光谱和时间测量应该有助于我们在仔细检查这些新的排放模型,在我们不断追求更深入地了解脉冲星的奇迹。

英文摘要:

The wealth of high-energy (E > 50 MeV) and very-high-energy (E > 100 GeV) data accumulated over the past few years have provided unprecedented opportunities to probe pulsar emission models. The Fermi Large Area Telescope (LAT) has now detected over 200 gamma-ray pulsars of vastly different ages, providing an extensive dataset of spectra and light curves compared to a mere decade ago. Ground-based Cherenkov telescopes deepened our appreciation of the mysterious richness of the pulsar mechanism by a surprise detection of pulsed emission up to 1 TeV from the Crab pulsar. These discoveries position us to make real progress in pulsar theory. A number of studies have developed new and enhanced existing dissipative magnetohydrodynamical (MHD) and particle-in-cell (PIC) codes to solve the global electrodynamics and pursue fundamental questions about magnetospheric particle injection, acceleration, and radiation. While MHD models capture the global aspects of pulsar magnetospheres, the microphysics need to be probed self-consistently by PIC simulations. Some dissipative MHD models consider the current sheet (CS) as an important site for high-energy curvature radiation (CR), while early PIC results point to energy dissipation taking place in the CS, where particles are accelerated by magnetic reconnection and may possibly emit $γ$ rays via synchrotron radiation (SR). This is in marked contrast to some older local emission models that studied CR gamma rays produced in gaps nearer to the spinning neutron star. The universality of these results should become clearer as current computational restrictions are overcome and boundary conditions are refined. Continued and combined polarimetric, spectral, and temporal measurements should aid us in scrutinising these new emission models in our persistent pursuit of a deeper understanding of the pulsar marvel.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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