Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Orbital variation of the X-ray emission from the double neutron star
  binary J1537+1155   We observed the double neutron star binary (DNSB) containing PSR J1537+1155
(also known as B1534+12) with the Chandra X-ray Observatory. This is one of the
two DNSBs detected in X-rays and the only one where a hint of variability with
orbital phase was found (in the previous Chandra observation). Our follow-up
observation supports the earlier result: the distribution of photon arrival
times with orbital phase again shows a deficit around apastron. The
significance of the deficit in the combined dataset exceeds 99%. Such an
orbital light-curve suggests that the X-ray emission is seen only when neutron
star B passes through the equatorial pulsar wind of neutron star A. We describe
statistical tests we used to determine the significance of the deficit, and
conclusions that can be drawn from its existence, such as interaction of the
pulsar wind with the neutron star companion. We also provide better constrained
spectral model parameters obtained from the joint spectral fits to the data
from both observations. A power-law successfully fits the data, with best-fit
photon index Gamma=3.1pm0.4 and unabsorbed flux f=(3.2pm0.8)x10^-15 erg s-1cm-2
(0.3-8 keV range).

30
The categories of this paper are: q-alg
4
The categories of this paper are: cond-mat
26
The categories of this paper are: bayes-an
21
The categories of this paper are: adap-org
9
The categories of this paper are: nlin
2
The categories of this paper are: math
13
The categories of this paper are: quant-ph
37
The categories of this paper are: supr-con
7
The categories of this paper are: hep-th
1
The categories of this paper are: cs
36
The categories of this paper are: cmp-lg
25
The categories of this paper are: patt-sol
15
The categories of this paper are: nucl-ex
34
The categories of this paper are: chem-ph
27
The categories of this paper are: comp-gas
3
The categories of this paper are: physics