Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Transition Region Emission and Energy Input to Thermal Plasma During the
  Impulsive Phase of Solar Flares   The energy released in a solar flare is partitioned between thermal and
non-thermal particle energy and lost to thermal conduction and radiation over a
broad range of wavelengths. It is difficult to determine the conductive losses
and the energy radiated at transition region temperatures during the impulsive
phases of flares. We use UVCS measurements of O VI photons produced by 5 flares
and subsequently scattered by O VI ions in the corona to determine the 5.0 <
log T < 6.0 transition region luminosities. We compare them with the rates of
increase of thermal energy and the conductive losses deduced from RHESSI and
GOES X-ray data using areas from RHESSI images to estimate the loop volumes,
cross-sectional areas and scale lengths. The transition region luminosities
during the impulsive phase exceed the X-ray luminosities for the first few
minutes, but they are smaller than the rates of increase of thermal energy
unless the filling factor of the X-ray emitting gas is ~ 0.01. The estimated
conductive losses from the hot gas are too large to be balanced by radiative
losses or heating of evaporated plasma, and we conclude that the area of the
flare magnetic flux tubes is much smaller than the effective area measured by
RHESSI during this phase of the flares. For the 2002 July 23 flare, the energy
deposited by non-thermal particles exceeds the X-ray and UV energy losses and
the rate of increase of the thermal energy.

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The categories of this paper are: atom-ph
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The categories of this paper are: bayes-an
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The categories of this paper are: patt-sol
5
The categories of this paper are: gr-qc
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The categories of this paper are: ao-sci
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The categories of this paper are: comp-gas
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The categories of this paper are: plasm-ph
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The categories of this paper are: mtrl-th
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The categories of this paper are: chem-ph
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The categories of this paper are: math
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The categories of this paper are: stat
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The categories of this paper are: dg-ga
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The categories of this paper are: q-alg
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The categories of this paper are: quant-ph
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The categories of this paper are: hep-th
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The categories of this paper are: eess