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Title: Solar flare accelerates nearly all electrons in a large coronal volume
Abstract Solar flares, driven by prompt release of free magnetic energy in the solar corona 1,2 , are known to accelerate a substantial portion (ten per cent or more) 3,4 of available electrons to high energies. Hard X-rays, produced by high-energy electrons accelerated in the flare 5 , require a high ambient density for their detection. This restricts the observed volume to denser regions that do not necessarily sample the entire volume of accelerated electrons 6 . Here we report evolving spatially resolved distributions of thermal and non-thermal electrons in a solar flare derived from microwave observations that show the true extent of the acceleration region. These distributions show a volume filled with only (or almost only) non-thermal electrons while being depleted of the thermal plasma, implying that all electrons have experienced a prominent acceleration there. This volume is isolated from a surrounding, more typical flare plasma of mainly thermal particles with a smaller proportion of non-thermal electrons. This highly efficient acceleration happens in the same volume in which the free magnetic energy is being released 2 .  more » « less
Award ID(s):
2121632 1817277 1654382 2108853 2130832
NSF-PAR ID:
10344799
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Nature
Volume:
606
Issue:
7915
ISSN:
0028-0836
Page Range / eLocation ID:
674 to 677
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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