Particle acceleration in multiple dissipation regions

被引:46
作者
Arzner, K [1 ]
Vlahos, L
机构
[1] Paul Scherrer Inst, Astrophys Lab, Dept Particles & Matter, CH-5232 Villigen, Switzerland
[2] Aristotle Univ Thessaloniki, Astron Inst, Dept Phys, Thessaloniki 54124, Greece
关键词
acceleration of particles; turbulence;
D O I
10.1086/392506
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
The sharp magnetic discontinuities that naturally appear in solar magnetic flux tubes driven by turbulent photospheric motions are associated with intense currents. Parker proposed that these currents can become unstable to a variety of microscopic processes, with the net result of dramatically enhanced resistivity and heating (nanoflares). The electric fields associated with such "hot spots" are also expected to enhance particle acceleration. We test this hypothesis by exact relativistic orbit simulations in strong random phase magnetohydrodynamic turbulence that is forming localized super-Dreicer Ohm electric fields (10(2) less than or equal to E-Omega/E-D less than or equal to 10(5)) occurring in 2% - 15% of the volume. It is found that these fields indeed yield a large amplification of acceleration of electrons and ions and can effectively overcome the injection problem. We suggest in this article that nanoflare heating will be associated with sporadic particle acceleration.
引用
收藏
页码:L69 / L72
页数:4
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