Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Plasma Waves near the Electron Cyclotron Frequency in the near-Sun Solar
  Wind   Data from the first two orbits of the Sun by Parker Solar Probe reveal that
the solar wind sunward of 50 solar radii is replete with plasma waves and
instabilities. One of the most prominent plasma wave power enhancements in this
region appears near the electron cyclotron frequency (f_ce). Most of this wave
power is concentrated in electric field fluctuations near 0.7 f_ce and f_ce,
with strong harmonics of both frequencies extending above f_ce. At least two
distinct, often concurrent, wave modes are observed, preliminarily identified
as electrostatic whistler-mode waves and electron Bernstein waves. Wave
intervals range in duration from a few seconds to hours. Both the amplitudes
and number of detections of these near-f_ce waves increase significantly with
decreasing distance to the Sun, suggesting that they play an important role in
the evolution of electron populations in the near-Sun solar wind. Correlations
are found between the detection of these waves and properties of solar wind
electron populations, including electron core drift, implying that these waves
play a role in regulating the heat flux carried by solar wind electrons.
Observation of these near-f_ce waves is found to be strongly correlated with
near-radial solar wind magnetic field configurations with low levels of
magnetic turbulence. A scenario for the growth of these waves is presented
which implies that regions of low-turbulence near-radial magnetic field are a
prominent feature of solar wind structure near the Sun.

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The categories of this paper are: solv-int
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The categories of this paper are: funct-an
16
The categories of this paper are: stat
12
The categories of this paper are: nucl-th
36
The categories of this paper are: cmp-lg
1
The categories of this paper are: cs
9
The categories of this paper are: nlin
18
The categories of this paper are: econ
25
The categories of this paper are: patt-sol
34
The categories of this paper are: chem-ph
8
The categories of this paper are: hep-ex
33
The categories of this paper are: plasm-ph
4
The categories of this paper are: cond-mat
31
The categories of this paper are: ao-sci
11
The categories of this paper are: hep-lat
10
The categories of this paper are: q-bio