arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1907.04296astro-ph.SR
收藏

磁通量出射区的粒子加速和加热

Particle Acceleration and Heating in Regions of Magnetic Flux Emergence

Heinz Isliker, Vasilis Archontis, Loukas Vlahos

摘要:

太阳大气层中新出现的和先前存在的磁场之间的相互作用可以触发几种动力学现象,如喷发和喷流。在这种相互作用过程中的一个关键因素是大规模电流片的形成,并最终导致其分裂,从而导致产生强烈的湍流环境。在本文中,我们研究了新兴和环境磁场之间的相互作用(重联)的动力学方面。我们发现,自发破碎和分形电场的统计特性是负责有效的加热和加速的带电粒子,形成一个幂律尾在高能量的亚秒级的时间尺度。一部分能量化粒子从加速体积中逃逸,具有温度接近$150\,$ MK的超热分量,以及指数在-2和-3之间的幂律高能尾部。我们估计的能量空间中的传输系数从内部的碎片和分形电场的带电粒子的动力学,和分数输运方程的解决方案,作为适当的强湍流等离子体,同意与测试粒子模拟。我们还表明,加速机制是不相关的费米加速,和福克普朗克方程是不一致的,不适合作为一个输运模型。最后,我们解决的问题之间的相关性空间运输和能源空间的运输。我们的结果证实了观测报告的高能粒子(硬X射线,III型爆发和太阳高能粒子)在太阳喷流的排放。

英文摘要:

The interaction between emerging and pre-existing magnetic fields in the solar atmosphere can trigger several dynamic phenomena, such as eruptions and jets. A key element during this interaction is the formation of large scale current sheets and, eventually, their fragmentation that leads to the creation of a strongly turbulent environment. In this paper, we study the kinetic aspects of the interaction (reconnection) between emerging and ambient magnetic fields. We show that the statistical properties of the spontaneously fragmented and fractal electric fields are responsible for the efficient heating and acceleration of charged particles, which form a power law tail at high energies on sub-second time scales. A fraction of the energized particles escapes from the acceleration volume, with a super-hot component with temperature close to $150\,$MK, and with a power law high energy tail with index between -2 and -3. We estimate the transport coefficients in energy space from the dynamics of the charged particles inside the fragmented and fractal electric fields, and the solution of a fractional transport equation, as appropriate for a strongly turbulent plasma, agrees with the test particle simulations. We also show that the acceleration mechanism is not related to Fermi acceleration, and the Fokker Planck equation is inconsistent and not adequate as a transport model. Finally, we address the problem of correlations between spatial transport and transport in energy space. Our results confirm the observations reported for high energy particles (hard X-rays, type III bursts and solar energetic particles) during the emission of solar jets.

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。

↑