X-ray and Radio Variabilities of PSR J2032+4127 near Periastron

Research output: Contribution to journalArticlepeer-review

  • External authors:
  • C.-Y. Ng
  • W. C. G. Ho
  • E. V. Gotthelf
  • J. P. Halpern
  • Malcolm J. Coe
  • Andrew Lyne
  • K. S. Wood
  • M. Kerr

Abstract

We present X-ray and radio monitoring observations of the gamma-ray binary PSR J2032+4127/MT91 213 during its periastron passage in late 2017. Dedicated Chandra, XMM-Newton, NuSTAR X-ray observations and VLA radio observations of this long orbit (50 years), 143 ms pulsar/Be star system clearly revealed flux and spectral variability during the passage. The X-ray spectrum hardened near periastron, with a signicant decrease in the power-law photon index from Γ ≈ 2 to 1.2 and evidence of an increased absorption column density. We identied a possible spectral break at a few keV in the spectrum that suggests synchrotron cooling. A coincident radio and X-ray are occurred one week after periastron, which is possibly the result of the pulsar wind interacting with the Be stellar disk and generating synchrotron radiation. However, a multi-wavelength comparison indicate that the X-ray and radio spectra cannot be simply connected by a single power-law component. Hence, the emission in these two energy bands must originate from different particle populations.

Bibliographical metadata

Original languageEnglish
JournalThe Astrophysical Journal
Early online date5 Aug 2019
DOIs
Publication statusPublished - Aug 2019