Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A model of the steep power law spectra and high-frequency quasi-periodic
  oscillations in luminous black hole X-ray binaries   We propose a new model of the steep power law state of luminous black hole
X-ray binaries. The model uses the fact that at high luminosities, the inner
radii of radiation pressure dominated accretion discs are expected to i) become
effectively optically thin and ii) produce significant luminosities. The gas
temperature therefore rises sharply inwards, producing local saturated Compton
spectra with rapidly increasing peak energy. These spectra sum together to form
a steep power law tail to the spectrum. A given photon energy on this tail
corresponds to a narrow range in radius, so that local vertical oscillations of
the disc naturally produce high quality high-frequency quasi-periodic
oscillations (HFQPOs) in the hard X-ray band. The two lowest order modes have a
robust frequency ratio of ~1.53. This model explains the appearance of steep
power law spectra and HFQPOs at high luminosity, the 3:2 HFQPO frequency
ratios, and their association with the power law spectral component. We predict
an increase in QPO quality factor when the power spectrum is restricted to a
narrower photon energy band, and an increase in HFQPO frequency at higher X-ray
energies or lower luminosities. Future X-ray telescopes could detect additional
HFQPOs from higher order modes. We demonstrate how this model could be used to
measure black hole spin from HFQPOs, and qualitatively estimate the spin of GRO
J1655-40 as a/M ~ 0.4 - 0.7.

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The categories of this paper are: chem-ph
21
The categories of this paper are: adap-org
19
The categories of this paper are: eess
35
The categories of this paper are: mtrl-th
29
The categories of this paper are: funct-an
15
The categories of this paper are: nucl-ex
9
The categories of this paper are: nlin
16
The categories of this paper are: stat
18
The categories of this paper are: econ
4
The categories of this paper are: cond-mat
2
The categories of this paper are: math
0
The categories of this paper are: hep-ph
10
The categories of this paper are: q-bio
8
The categories of this paper are: hep-ex
28
The categories of this paper are: alg-geom
7
The categories of this paper are: hep-th