Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: XMM-Newton observations of the Small Magellanic Cloud: X-ray outburst of
  the 6.85 s pulsar XTE J0103-728   A bright X-ray transient was seen during an XMM-Newton observation in the
direction of the Small Magellanic Cloud (SMC) in October 2006. The EPIC data
allow us to accurately locate the source and to investigate its temporal and
spectral behaviour. X-ray spectra covering 0.2-10 keV and pulse profiles in
different energy bands were extracted from the EPIC data. The detection of 6.85
s pulsations in the EPIC-PN data unambiguously identifies the transient with
XTE J0103-728, discovered as 6.85 s pulsar by RXTE. The X-ray light curve
during the XMM-Newton observation shows flaring activity of the source with
intensity changes by a factor of two within 10 minutes. Modelling of
pulse-phase averaged spectra with a simple absorbed power-law indicates
systematic residuals which can be accounted for by a second emission component.
For models implying blackbody emission, thermal plasma emission or emission
from the accretion disk (disk-blackbody), the latter yields physically sensible
parameters. The photon index of the power-law of ~0.4 indicates a relatively
hard spectrum. The 0.2-10 keV luminosity was 2x10^{37} with a contribution of
~3% from the disk-blackbody component. A likely origin for the excess emission
is reprocessing of hard X-rays from the neutron star by optically thick
material near the inner edge of an accretion disk. From a timing analysis we
determine the pulse period to 6.85401(1) s indicating an average spin-down of
~0.0017 s per year since the discovery of XTE J0103-728 in May 2003. The X-ray
properties and the identification with a Be star confirm XTE J0103-728 as
Be/X-ray binary transient in the SMC.

9
The categories of this paper are: nlin
14
The categories of this paper are: math-ph
7
The categories of this paper are: hep-th
8
The categories of this paper are: hep-ex
29
The categories of this paper are: funct-an
4
The categories of this paper are: cond-mat
27
The categories of this paper are: comp-gas
17
The categories of this paper are: q-fin
16
The categories of this paper are: stat
36
The categories of this paper are: cmp-lg
12
The categories of this paper are: nucl-th
11
The categories of this paper are: hep-lat
0
The categories of this paper are: hep-ph
32
The categories of this paper are: atom-ph
28
The categories of this paper are: alg-geom
35
The categories of this paper are: mtrl-th