Show simple item record  

dc.contributor.authorLitvinenko, Yuri E.
dc.contributor.authorSchlickeiser, Reinhard
dc.date.accessioned2011-08-10T02:44:45Z
dc.date.available2011-08-10T02:44:45Z
dc.date.issued2011
dc.identifier.citationLitvinenko, Y.E. & Schlickeiser, R. (2011). Focused acceleration of cosmic-ray particles in non-uniform magnetic fields. The Astrophysical Journal Letters, 732 (L31).en_NZ
dc.identifier.urihttps://hdl.handle.net/10289/5558
dc.description.abstractThe Fokker–Planck equation for cosmic-ray particles in a spatially varying guide magnetic field in a turbulent plasma is analyzed. An expression is derived for the mean rate of change of particle momentum, caused by the effect of adiabatic focusing in a non-uniform guide field. Results of an earlier diffusion-limit analysis are confirmed, and the physical picture is clarified by working directly with the Fokker–Planck equation. A distributed first-order Fermi acceleration mechanism is identified, which can be termed focused acceleration. If the forward and backward-propagating waves have equal polarizations, focused acceleration operates when the net cross helicity of an Alfvenic slab turbulence is either negative in a diverging guide field or positive in a converging guide field. It is suggested that focused acceleration can contribute to the formation of the anomalous cosmic-ray spectrum at the heliospheric termination shock.en_NZ
dc.format.mimetypeapplication/pdf
dc.language.isoen
dc.publisherThe American Astronomical Societyen_NZ
dc.relation.urihttp://iopscience.iop.org/2041-8205/732/2/L31/pdf/2041-8205_732_2_L31.pdfen_NZ
dc.rightsThis article has been published in the journal: The Astrophysical Journal Letters. © 2011 The American Astronomical Society.en_NZ
dc.subjectacceleration of particlesen_NZ
dc.subjectcosmic raysen_NZ
dc.subjectturbulenceen_NZ
dc.titleFocused acceleration of cosmic-ray particles in non-uniform magnetic fieldsen_NZ
dc.typeJournal Articleen_NZ
dc.identifier.doi10.1088/2041-8205/732/2/L31en_NZ
dc.relation.isPartOfThe Astrophysical Journal Lettersen_NZ
pubs.begin-page1en_NZ
pubs.elements-id36207
pubs.end-page5en_NZ
pubs.issue2en_NZ
pubs.volume732en_NZ


Files in this item

This item appears in the following Collection(s)

Show simple item record