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Title: Multiwavelength monitoring and X-ray brightening of Be X-ray binary PSR J2032+4127/MT91 213 on its approach to periastron

The radio and gamma-ray pulsar PSR J2032+4127 was recently found to be in a decades-long orbit with the Be star MT91 213, with the pulsar moving rapidly towards periastron. This binary shares many similar characteristics with the previously unique binary system PSR B1259-63/LS 2883. Here in this paper, we describe radio, X-ray, and optical monitoring of PSR J2032+4127/MT91 213. Our extended orbital phase coverage in radio, supplemented with Fermi LAT gamma-ray data, allows us to update and refine the orbital period to 45–50 yr and time of periastron passage to 2017 November. We analyse archival and recent Chandra and Swift observations and show that PSR J2032+4127/MT91 213 is now brighter in X-rays by a factor of ~70 since 2002 and ~20 since 2010. While the pulsar is still far from periastron, this increase in X-rays is possibly due to collisions between pulsar and Be star winds. Optical observations of the Hα emission line of the Be star suggest that the size of its circumstellar disc may be varying by ~2 over time-scales as short as 1–2 months. In conclusion, multiwavelength monitoring of PSR J2032+4127/MT91 213 will continue through periastron passage, and the system should present an interesting test case andmore » comparison to PSR B1259-63/LS 2883.« less
 [1] ;  [2] ;  [3] ;  [3] ;  [4] ;  [5] ;  [6] ;  [7]
  1. University of Southampton (United Kingdom). Mathematical Sciences and STAG Research Centre and Physics and Astronomy and STAG Research Centre
  2. University of Hong Kong (China). Department of Physics
  3. Univ. of Manchester (United Kingdom). Jodrell Bank Centre for Astrophysics, School of Physics and Astronomy
  4. University of Southampton (United Kingdom). Physics and Astronomy and STAG Research Centre
  5. Columbia Univ., New York, NY (United States). Columbia Astrophysics Lab.
  6. George Mason Univ., Fairfax, VA (United States). College of Science
  7. Liverpool John Moores University (United Kingdom). Astrophysics Research Institute
Publication Date:
Grant/Contract Number:
Accepted Manuscript
Journal Name:
Monthly Notices of the Royal Astronomical Society
Additional Journal Information:
Journal Volume: 464; Journal Issue: 1; Journal ID: ISSN 0035-8711
Royal Astronomical Society
Research Org:
SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Org:
Contributing Orgs:
Fermi LAT Collaboration
Country of Publication:
United States
79 ASTRONOMY AND ASTROPHYSICS; stars; emission line; Be; individual; MT91 213; neutron; pulsars; PSR B1259−63; PSR J2032+4127; X-rays; binaries
OSTI Identifier: