Radio detection of LAT PSRs J1741-2054 and J2032+4127: no longer just gamma-ray pulsars

F. Camilo; P. S. Ray; S. M. Ransom; M. Burgay; T. J. Johnson; M. Kerr; E. V. Gotthelf; J. P. Halpern; J. Reynolds; R. W. Romani; P. Demorest; S. Johnston; W. van Straten; P. M. Saz Parkinson; M. Ziegler; M. Dormody; D. J. Thompson; D. A. Smith; A. K. Harding; A. A. Abdo; F. Crawford; P. C. C. Freire; M. Keith; M. Kramer; M. S. E. Roberts; P. Weltevrede; K. S. Wood

doi:10.1088/0004-637x/705/1/1

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arXiv · 0908.2626

Radio detection of LAT PSRs J1741-2054 and J2032+4127: no longer just gamma-ray pulsars

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Abstract

Sixteen pulsars have been discovered so far in blind searches of photons collected with the Large Area Telescope on the Fermi Gamma-ray Space Telescope. We here report the discovery of radio pulsations from two of them. PSR J1741-2054, with period P=413ms, was detected in archival Parkes telescope data and subsequently has been detected at the Green Bank Telescope (GBT). Its received flux varies greatly due to interstellar scintillation and it has a very small dispersion measure of DM=4.7pc/cc, implying a distance of ~0.4kpc and possibly the smallest luminosity of any known radio pulsar. At this distance, for isotropic emission, its gamma-ray luminosity above 0.1GeV corresponds to 25% of the spin-down luminosity of dE/dt=9.4e33erg/s. The gamma-ray profile occupies 1/3 of pulse phase and has three closely-spaced peaks with the first peak lagging the radio pulse by delta=0.29P. We have also identified a soft Swift source that is the likely X-ray counterpart. In many respects PSR J1741-2054 resembles the Geminga pulsar. The second source, PSR J2032+4127, was detected at the GBT. It has P=143ms, and its DM=115pc/cc suggests a distance of ~3.6kpc, but we consider it likely that it is located within the Cyg OB2 stellar association at half that distance. The radio emission is nearly 100% linearly polarized, and the main radio peak precedes by delta=0.15P the first of two narrow gamma-ray peaks that are separated by Delta=0.50P. Faint, diffuse X-ray emission in a Chandra image is possibly its pulsar wind nebula. PSR J2032+4127 likely accounts for the EGRET source 3EG J2033+4118, while its pulsar wind is responsible for the formerly unidentified HEGRA source TeV J2032+4130.

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F. Camilo, P. S. Ray, S. M. Ransom, M. Burgay, T. J. Johnson, M. Kerr, E. V. Gotthelf, J. P. Halpern, J. Reynolds, R. W. Romani, P. Demorest, S. Johnston, W. van Straten, P. M. Saz Parkinson, M. Ziegler, M. Dormody, D. J. Thompson, D. A. Smith, A. K. Harding, A. A. Abdo, F. Crawford, P. C. C. Freire, M. Keith, M. Kramer, M. S. E. Roberts, P. Weltevrede, K. S. Wood. 2009-08-18. Radio detection of LAT PSRs J1741-2054 and J2032+4127: no longer just gamma-ray pulsars. https://doi.org/10.1088/0004-637x/705/1/1

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