Astronomy and Astrophysics – Astrophysics
Scientific paper
Oct 2001
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2001a%26a...378..309v&link_type=abstract
Astronomy and Astrophysics, v.378, p.309-315 (2001)
Astronomy and Astrophysics
Astrophysics
4
Acceleration Of Particles, Shock Waves, Turbulence
Scientific paper
Alfvén-wave transmission through a parallel shock in case of an anisotropic gas pressure (Pparallel!=q Pperpendicular to is considered from the point of view of test particle acceleration in such shock waves. Treating the shock's gas compression ratio and the firehose factor, phi =1-4pi (Pparallel-Pperpendicular to) /B2 , on both sides of the shock as given parameters, we calculate the wave-transmission coefficients for circularly-polarized Alfvén waves of finite amplitude. We also give an equation for the shock's gas compression ratio including the effects of pressure anisotropy and waves. We study wave transmission and test-particle acceleration in a model, where the downstream plasma is isotropic and the upstream plasma remains stable against the firehose instability ( phi >0 ). The results can be arranged in a following manner with respect to the upstream parallel plasma beta, betaparallel equiv 8pi Pparallel/B02 (with B0 being the ordered magnetic field): (i) for shocks with betaparallel << 2 the results for particle acceleration are only quantitatively different for anisotropic upstream plasma; (ii) for betaparallel ~ 2 , large anisotropies alter the wave-transmission and particle acceleration picture completely relative to the isotropic case yielding much harder energy spectra with spectral indices 1
Schlickeiser Reinhard
Vainio Rami
No associations
LandOfFree
The effect of anisotropic gas pressure on Alfvén-wave transmission and test-particle acceleration at parallel shock waves does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with The effect of anisotropic gas pressure on Alfvén-wave transmission and test-particle acceleration at parallel shock waves, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The effect of anisotropic gas pressure on Alfvén-wave transmission and test-particle acceleration at parallel shock waves will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1099940