The evolution of slab fluctuations in the presence of pressure-balanced magnetic structures and velocity shears

Details The evolution of slab fluctuations in the presence of pressure-balanced magnetic structures and velocity shears The evolution of slab fluctuations in the presence of pressure-balanced magnetic structures and velocity shears

Oct 1998

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1998jgr...10323691g&link_type=abstract

Journal of Geophysical Research, Volume 103, Issue A10, p. 23691-23704

Physics

27

Interplanetary Physics: Mhd Waves And Turbulence

Scientific paper

The traditional view that solar wind fluctuations are well-described as a spectrum of parallel-propagating Alfvén waves has been challenged many times but is still a frequently encountered perspective. Here we examine whether it remains consistent to view most of the fluctuation energy as resident in parallel-propagating Alfvén waves in situations in which there are also present either transverse pressure-balanced (PB) magnetic structures or transverse velocity shears. We address these questions through direct simulation of compressible magnetohydrodynamics, with expansion effects neglected. We show that parallel-propagating Alfvén waves are redirected to large oblique angles after refractive interactions with PB structures or advective interactions with velocity shears, reflecting the nonequilibrium nature of the initial spectral distribution. The timescale for these processes ranges from 2-8 eddy-turnover times or characteristic nonlinear times. Relatively small amounts of PB structure and/or shear energy can redirect initially parallel-propagating Alfvén waves to highly oblique angles. Velocity microstreams appear to be particularly efficient at creating highly oblique waves. Even though the excited wave vectors are eventually primarily oblique, the magnetic variance ratios show a minimum variance in the mean magnetic field direction.

Affiliated with

Also associated with

No associations

Rating

The evolution of slab fluctuations in the presence of pressure-balanced magnetic structures and velocity shears 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 evolution of slab fluctuations in the presence of pressure-balanced magnetic structures and velocity shears, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The evolution of slab fluctuations in the presence of pressure-balanced magnetic structures and velocity shears will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1097972