Proton temperature anisotropy upper bound

Details Proton temperature anisotropy upper bound Proton temperature anisotropy upper bound

Dec 1997

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1997jgr...10227159g&link_type=abstract

Journal of Geophysical Research, Volume 102, Issue A12, p. 27159-27170

Physics

Plasma Physics

53

Magnetospheric Physics: Magnetosheath, Magnetospheric Physics: Numerical Modeling, Magnetospheric Physics: Plasma Waves And Instabilities, Space Plasma Physics: Kinetic And Mhd Theory

Scientific paper

The electromagnetic proton cyclotron instability and the mirror instability are driven by the proton temperature anisotropy T⊥p/T∥p>1, where ⊥ and ∥ denote directions relative to the background magnetic field. Linear theory and one-dimensional hybrid simulations imply that the former mode grows more rapidly over 0.05<=β∥p<=5 and that wave-particle scattering by its enhanced fluctuations imposes an upper bound on the temperature anisotropy of the form T⊥p/T∥p-1=Sp/β∥pαp where β∥p≡8πnpT∥p/Bo2 and Bo is the background magnetic field. Here Sp and αp are fitting parameters, and 0.4<~αp<~0.5. This paper describes results from more general two-dimensional hybrid simulations, which permit both instabilities to grow simultaneously. These simulations confirm the one-dimensional results on the initial domain 0.05<=β∥p<~5 enhanced fluctuations display the properties of the proton cyclotron instability and αp~=0.4. On this domain the two-dimensional simulations also yield an upper bound for the fluctuating field energy density of the form |δB|2/Bo2≡∑k|δBk|2/Bo2=SBβ∥pαB with fitting parameter 0.5<~αB<~1. The simulations on the initial domain 10<=β∥p<=100 show spectral characteristics of both instabilities and exhibit a more stringent bound on the proton anisotropy, in agreement with observations in the terrestrial magnetosheath.

Affiliated with

Also associated with

No associations

Rating

Proton temperature anisotropy upper bound 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 Proton temperature anisotropy upper bound, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Proton temperature anisotropy upper bound will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1662102