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

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. Keith; 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

doi:10.1088/0004-637x/732/1/47

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arXiv · 1102.4192

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

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Abstract

We report the discovery of two millisecond pulsars in a search for radio pulsations at the positions of \emph{Fermi Large Area Telescope} sources with no previously known counterparts, using the Nan\c{c}ay radio telescope. The two millisecond pulsars, PSRs J2017+0603 and J2302+4442, have rotational periods of 2.896 and 5.192 ms 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 \emph{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 PSR J2302+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 \emph{Fermi} sources with no known counterpart could be unknown millisecond pulsars.

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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. Keith, 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. 2011-02-21. Discovery of two millisecond pulsars in Fermi sources with the Nancay Radio Telescope. https://doi.org/10.1088/0004-637x%2F732%2F1%2F47

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