Orbital variation of the X-ray emission from the double neutron star binary J1537+1155

Martin Durant, Oleg Kargaltsev, Igor Volkov, George G. Pavlov

Research output: Contribution to journalArticlepeer-review

3 Scopus citations


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 data set exceeds 99%. Such an orbital light curve suggests that the X-ray emission is seen only when neutron star (NS) B passes through the equatorial pulsar wind of NS A. We describe statistical tests that 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 NS 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 Γ = 3.1 0.4 and unabsorbed flux f = (3.2 0.8) × 10-15 ergs-1 cm-2 (0.3-8keV range).

Original languageEnglish (US)
Article number65
JournalAstrophysical Journal
Issue number1
StatePublished - Nov 1 2011

All Science Journal Classification (ASJC) codes

  • Astronomy and Astrophysics
  • Space and Planetary Science


Dive into the research topics of 'Orbital variation of the X-ray emission from the double neutron star binary J1537+1155'. Together they form a unique fingerprint.

Cite this