STOCHASTIC ACCELERATION OF COSMIC RAYS IN STOCHASTIC ACCELERATION OF COSMIC RAYS IN ANISOTROPIC PLASMA TURBULENCEANISOTROPIC PLASMA TURBULENCE

Yurij FedorovYurij Fedorov11, and Milan Stehlik, and Milan Stehlik22

1Main Astronomical Observatory NASU, Kiev, Ukraine2Institute of Experimental Physics SAS, Košice, Slovakia

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F ig .4 . T h e e n e rg e t ic s p e c tra c o r re s p o n d in g to th e s te a d y s ta te s o lu t io n (1 1 ) ,(1 2 ) .

N u m b e rs n e a r c u rv e s c o r re s p o n d to d im e n s io n le s s p a ra m e te r e = t e / t 0 .

T h e m o m e n tu m d if fu s io n c o e f f ic ie n t is g iv e n b y e q u a t io n (5 ) ; = 0 .5 .

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F ig .5 . T h e e n e r g e t ic s p e c t r a c o r r e s p o n d in g to th e s te a d y s ta te s o lu t io n ( 1 1 ) ,( 1 2 ) .

N u m b e r s n e a r c u r v e s c o r r e s p o n d to d im e n s io n le s s p a r a m e te r e = t e / t 0 .

T h e m o m e n tu m d i f f u s io n c o e f f ic ie n t i s g iv e n b y e q u a t io n ( 6 ) ; = 0 .5 .

1 0-1

1 00

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Fig.7. The differential proton spectra on June 15, 1991 GLE

(Belov, Eroshenko, 1996).

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N u m b er n ea r cu rv es d en o te d im en sio n less tim e; D p = D F ; = 0 .5 .

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F ig .1 0 . T h e s p e c tra o f e n e rg e t ic p a r t ic le s u n d e r m o n o e n e rg e t ic in je c t io n .

N u m b e r n e a r c u rv e s d e n o te d im e n s io n le s s t im e ; D p = D k ; = 0 .5 .

1 0-1

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ConclusionsConclusions

Particle acceleration by large scale EF can Particle acceleration by large scale EF can be efficient for a medium of sufficiently be efficient for a medium of sufficiently high magnetic helicityhigh magnetic helicity

The results can be useful for description of The results can be useful for description of particle acceleration in astrophysical particle acceleration in astrophysical objects ( solar flares, supernova remnants, objects ( solar flares, supernova remnants, galactic nuclei, … )galactic nuclei, … )

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