Discovery of two millisecond pulsars in Fermi sources with the Nançay Radio Telescope

Research output: Contribution to journalArticle

  • External authors:
  • I. Cognard
  • L. Guillemot
  • T. J. Johnson
  • D. A. Smith
  • C. Venter
  • A. K. Harding
  • M. T. Wolff
  • C. C. Cheung
  • D. Donato
  • A. A. Abdo
  • J. Ballet
  • F. Camilo
  • G. Desvignes
  • D. Dumora
  • E. C. Ferrara
  • P. C C Freire
  • J. E. Grove
  • S. Johnston
  • M. Kramer
  • A. G. Lyne
  • P. F. Michelson
  • D. Parent
  • S. M. Ransom
  • P. S. Ray
  • R. W. Romani
  • P. M Saz Parkinson
  • B. W. Stappers
  • G. Theureau
  • D. J. Thompson
  • P. Weltevrede
  • K. S. Wood


We report the discovery of two millisecond pulsars in a search for radio pulsations at the positions of Fermi-Large Area Telescope sources with no previously known counterparts, using the Nançay Radio Telescope. The two millisecond pulsars, PSRs J2017+0603 and J2302+4442, have rotational periods of 2.896 and 5.192ms and are both in binary systems with low-eccentricity orbits and orbital periods of 2.2 and 125.9 days, respectively, suggesting long recycling processes. Gamma-ray pulsations were subsequently detected for both objects, indicating that they power the associated Fermi sources in which they were found. The gamma-ray light curves and spectral properties are similar to those of previously detected gamma-ray millisecond pulsars. Detailed modeling of the observed radio and gamma-ray light curves shows that the gamma-ray emission seems to originate at high altitudes in their magnetospheres. Additionally, X-ray observations revealed the presence of an X-ray source at the position of PSRJ2302+4442, consistent with thermal emission from a neutron star. These discoveries along with the numerous detections of radio-loud millisecond pulsars in gamma rays suggest that many Fermi sources with no known counterpart could be unknown millisecond pulsars. © 2011. The American Astronomical Society. All rights reserved.

Bibliographical metadata

Original languageEnglish
Article number47
JournalAstrophysical Journal
Issue number1
Publication statusPublished - 1 May 2011