Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Cygnus X-1: A Case for a Magnetic Accretion Disk?   With the advent of RXTE, which is capable of broad spectral coverage and fast
timing, as well as other instruments which are increasingly being used in
multi-wavelength campaigns (via both space-based and ground-based
observations), we must demand more of our theoretical models. No current model
mimics all facets of a system as complex as an x-ray binary. However, a modern
theory should qualitatively reproduce -- or at the very least not fundamentally
disagree with - all of Cygnus X-1's most basic average properties: energy
spectrum (viewed within a broader framework of black hole candidate spectral
behavior), power spectrum (PSD), and time delays and coherence between
variability in different energy bands. Below we discuss each of these basic
properties in turn, and we assess the health of one of the currently popular
theories: Comptonization of photons from a cold disk. We find that the data
pose substantial challenges for this theory, as well as all other currently
discussed models.

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The categories of this paper are: patt-sol
3
The categories of this paper are: physics
0
The categories of this paper are: hep-ph
29
The categories of this paper are: funct-an
4
The categories of this paper are: cond-mat
15
The categories of this paper are: nucl-ex
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The categories of this paper are: comp-gas
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The categories of this paper are: supr-con
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The categories of this paper are: quant-ph
1
The categories of this paper are: cs
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The categories of this paper are: econ
11
The categories of this paper are: hep-lat
31
The categories of this paper are: ao-sci
20
The categories of this paper are: acc-phys
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The categories of this paper are: eess
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The categories of this paper are: q-fin