Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Evolution of spectral parameters during a pre-eclipse dip of Her X-1   We report on a pre-eclipse dip of the X-ray binary Her X-1 observed by the
Rossi X-ray Timing Explorer (RXTE) in July 1996. We present the evolution of
the spectral parameters in the 3-18 keV range with a temporal resolution of 16
s and show that the varying flux of the spectrum can be interpreted solely by a
time varying column density. We also find that the lightcurve is characterized
by symmetric substructures with recurrence time of a few minutes that can be
successfully modeled by Gaussian profiles.

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The categories of this paper are: comp-gas
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The categories of this paper are: econ
25
The categories of this paper are: patt-sol
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The categories of this paper are: dg-ga
5
The categories of this paper are: gr-qc
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The categories of this paper are: solv-int
3
The categories of this paper are: physics
1
The categories of this paper are: cs
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The categories of this paper are: bayes-an
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The categories of this paper are: adap-org
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The categories of this paper are: ao-sci
4
The categories of this paper are: cond-mat
0
The categories of this paper are: hep-ph
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The categories of this paper are: cmp-lg
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The categories of this paper are: acc-phys
12
The categories of this paper are: nucl-th