Observation of energetic electrons within magnetic islands

被引：244

作者：

Chen, L. -J. ^{[1
]}

Bhattacharjee, A. ^{[1
]}

Puhl-Quinn, P. A. ^{[1
]}

Yang, H. ^{[1
]}

Bessho, N. ^{[1
]}

Imada, S. ^{[2
]}

Muehlbachler, S.

Daly, P. W. ^{[3
]}

Lefebvre, B. ^{[3
,4
]}

Khotyaintsev, Y. ^{[5
]}

Vaivads, A. ^{[5
]}

Fazakerley, A. ^{[6
]}

Georgescu, E. ^{[7
]}

机构：

[1] Univ New Hampshire, Ctr Space Sci, Durham, NH 03824 USA

[2] Natl Astron Observ, Tokyo 1818588, Japan

[3] Max Planck Inst Solar Syst Res, D-37191 Katlenburg Lindau, Germany

[4] Univ London Imperial Coll Sci Technol & Med, Blackett Lab, London SW7 2BW, England

[5] Swedish Inst Space Phys, SE-75121 Uppsala, Sweden

[6] UCL, Mullard Space Sci Lab, Dorking RH5 6NT, Surrey, England

[7] Max Planck Inst Extraterr Phys, D-85741 Garching, Germany

来源：

NATURE PHYSICS | 2008年 / 4卷 / 01期

基金：

英国科学技术设施理事会;

关键词：

D O I：

10.1038/nphys777

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

Magnetic reconnection is the underlying process that releases impulsively an enormous amount of magnetic energy(1) in solar flares(2,3), flares on strongly magnetized neutron stars(4) and substorms in the Earth's magnetosphere(5). Studies of energy release during solar flares, in particular, indicate that up to 50% of the released energy is carried by accelerated 20-100 keV suprathermal electrons(6-8). How so many electrons can gain so much energy during reconnection has been a long-standing question. A recent theoretical study suggests that volume-filling contracting magnetic islands formed during reconnection can produce a large number of energetic electrons(9). Here we report the first evidence of the link between energetic electrons and magnetic islands during reconnection in the Earth's magnetosphere. The results indicate that energetic electron fluxes peak at sites of compressed density within islands, which imposes a new constraint on theories of electron acceleration.

引用

页码：19 / 23

页数：5

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