TITLE:
Two Stream Instability as a Source of Coronal Heating
AUTHORS:
Antony Soosaleon, Blesson Jose
KEYWORDS:
Coronal Heating, Two Stream Instability, Langmuir Waves, Ion Temperature, Drift Velocity, Photosphere, Fusion Plasma
JOURNAL NAME:
International Journal of Astronomy and Astrophysics,
Vol.5 No.2,
May
4,
2015
ABSTRACT: Recent
observation of oscillating the two stream instability (TSI) in a solar type III
radio bursts and spatial damping of Langmuir oscillations has made this
instability as an important candidate to understand the coronal heating problem.
This instability has been studied by several authors for cold plasma found to
be stable for high frequencies (greater than plasma frequency ωp). In this paper, we prove that
this instability is unstable for warm plasma for higher frequencies (greater
than plasma frequency ωp)
and much suitable to study the solar coronal heating problem. We have derived a
general dispersion relation for warm plasma and discussed the various methods
analyzing the instability conditions. Also, we derived an expression for the
growth rate of TSI and analyzed the growth rate for photospheric and coronal plasmas.
A very promising result is that the ion temperature is the source of this
instability and shifts the growth rate to high frequency region, while the
electron temperature does the reverse. TSI shows a high growth rate for a wide
frequency range for photosphere plasma, suggesting that the electron
precipitation by magnetic reconnection current, acceleration by flares, may be
source of TSI in the photosphere. But for corona, these waves are damped to
accelerate the ions and further growing of such instability is prohibited due
to the high conductivity in coronal plasma. The TSI is a common instability;
the theory can be easily modifiable for multi-ion plasmas and will be a useful
tool to analyze all the astrophysical problems and industrial devices, too.