Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Effect of Mass Fluctuation on Collective Modes in a Dusty Plasma   The grains immersed in plasma get eroded by the ions falling onto them. As a
consequence, they exhibit self-consistent mass fluctuations due to
perturbations in the plasma charging currents. The grain mass is then a
dynamical variable. The modifications in the plasma dielectric properties are
investigated and new ultra-low frequency modes are shown to exist in the
plasma.

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The categories of this paper are: atom-ph
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The categories of this paper are: ao-sci
23
The categories of this paper are: solv-int
4
The categories of this paper are: cond-mat
18
The categories of this paper are: econ
7
The categories of this paper are: hep-th
15
The categories of this paper are: nucl-ex
25
The categories of this paper are: patt-sol
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The categories of this paper are: chem-ph
6
The categories of this paper are: astro-ph
5
The categories of this paper are: gr-qc
16
The categories of this paper are: stat
1
The categories of this paper are: cs
11
The categories of this paper are: hep-lat
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The categories of this paper are: cmp-lg
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The categories of this paper are: q-alg