Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Electric field filamentation and higher harmonic generation in a very
  high frequency capacitive discharges   The effects of the discharge voltage on the formation and nature of electric
field transients in a symmetric, collisionless, very high frequency,
capacitively coupled plasma are studied using a self-consistent
particle-in-cell (PIC) simulation code. At a driving frequency of 60 MHz and 5
mTorr of argon gas pressure, the discharge voltage is varied from 10V to 150 V
for a fixed discharge gap. It is observed that an increase in the discharge
voltage causes filamentation in the electric field transients and to create
multiple higher harmonics in the bulk plasma. Correspondingly, higher
harmonics, up to 7th harmonic, in the discharge current are also observed. The
power in the higher harmonics increases with a rise in the discharge voltage.
The plasma density continues to increase with the discharge voltage but in a
non-linear manner, whereas, the bulk electron temperature decreases. Meanwhile,
the electron energy distribution function (EEDF) evolves from a Maxwellian at
lower discharge voltages to a bi-Maxwellian at higher discharge voltages.

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The categories of this paper are: gr-qc
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The categories of this paper are: hep-th
31
The categories of this paper are: ao-sci
2
The categories of this paper are: math
18
The categories of this paper are: econ
22
The categories of this paper are: chao-dyn
15
The categories of this paper are: nucl-ex
13
The categories of this paper are: quant-ph
10
The categories of this paper are: q-bio
14
The categories of this paper are: math-ph
32
The categories of this paper are: atom-ph
9
The categories of this paper are: nlin
25
The categories of this paper are: patt-sol
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The categories of this paper are: hep-ph
37
The categories of this paper are: supr-con
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The categories of this paper are: hep-ex