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FIZIKA B 16 (2007) 1, 39 - 48
 
LINEAR WAVES IN A SELF-GRAVITATING DUSTY PLASMA WITH DUST
CHARGE FLUCTUATION
K. K. MONDAL
Department of Physics, Raja Peary Mohan College, Uttarpara,
Hooghly, West Bengal India, Pin-712258
E-mail address: kalyan_mondal@vsnl.net
Received 25 October 2004; Revised manuscript received 11 December 2006
Accepted 20 December 2006 Online 22 May 2007
In astrophysical environments, dynamics of large bodies such as planets,
stars and satellites is solely governed by gravitational force, whereas
electromagnetic force is the only force effective in controlling the dynamics of
electrons, ions. It is very interesting to note that for the micron and
submicron size dust grains these two forces become comparable, i.e. Gmd2/qd2
» O(1), and the interplay between the gravitational and the electrostatic forces
in the dynamics of such grains leads to various novel phenomena in the
terrestrial and solar environment. Our motivation is to study linear waves
excited in a dusty plasma due to self gravity. The constituents of our plasma
system are electrons, ions, and micron- and submicron-sized dust grains. We
consider this dusty plasma to be infinite, homogeneous with spatially uniform
densities of the species. The ratio G md2/q
d2 is very small for the electrons
and ions, and so the effects of self gravity for these species may be neglected.
Moreover, we have taken into account the ion-dynamics together with the
dust-dynamics and charge fluctuation of the dust grains. Then we have derived a
dispersion law associated with the analysis of the linear gravitational
instability of the waves. In our analysis, we disregard the zero-order
gravitational field and so Poisson's equation for the gravitational potential,
y, has to be modified. The dispersion law has been analysed in detail and
various cases are discussed.
PACS numbers: 36.40.Gk, 52.25.Zb, 52.35.-g
UDC 533.922, 533.951
Keywords: dusty plasma, gravitational and electrostatic force, linear waves,
charge fluctuation of the dust grains, dispersion law
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