Slow magnetoacoustic-like waves in post-flare loops

Details Slow magnetoacoustic-like waves in post-flare loops Slow magnetoacoustic-like waves in post-flare loops

Jun 2004

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2004a%26a...420.1107k&link_type=abstract

Astronomy and Astrophysics, v.420, p.1107-1115 (2004)

Astronomy and Astrophysics

Astrophysics

1

Plasmas, Sun: Flares, Sun: Chromosphere

Scientific paper

We investigate the stability to the development of plasma waves in the preflare situation of a loop structure at the chromospheric part of a current circuit of a loop. We investigate the conditions under which low-frequency plasma instabilities can develop, assuming the absence of beam instabilities.The large-scale quasi-static electric field in the loop circuit is assumed to be ``subdreicer" and weak. Thus the percentage of ``runaway" electrons is very small and their influence on the process of instability development is negligible. The pair Coulomb collisions are described by a BGK-model integral. We consider the situation when the plasma at the surface layer of a loop has a spatial gradient of density. In accordance with Heyvaerts-Priest-Rust theory, such a preflare situation would typically exist when the amplitude of the weak electric field | E0 (t) | in the circuit of an ``old" loop in an active region begins to increase when ``new" magnetic flux emerges from under the photosphere. We have found that two types of waves are generated in such a plasma due to the growth of instabilities: the ``kinetic Alfven-like" waves and new type of waves, in the range of magnetoacoustic ones. The instability of these latter waves has a clear threshold and it can be considered as an ``indicator" of the development of a preflare situation in an active region.

Affiliated with

Also associated with

No associations

Rating

Slow magnetoacoustic-like waves in post-flare loops 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 Slow magnetoacoustic-like waves in post-flare loops, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Slow magnetoacoustic-like waves in post-flare loops will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-889655