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arXiv · astro-ph/0402183

PSR J2021+3651: A New Gamma-Ray Pulsar Candidate

Abstract

The COS B high energy gamma-ray source 2CG 075+00, also known as GeV J2020+3658 or 3EG J2021+3716, has avoided identification with a low energy counterpart for over twenty years. We present a likely identification with the discovery and subsequent timing of a young and energetic pulsar, PSR J2021+3651, with the Wideband Arecibo Pulsar Processor at the Arecibo Observatory. PSR J2021+3651 has a rotation period P = 104ms and Pdot = 9.6 x 10^{-14}, implying a characteristic age T_c = 17kyr and a spin-down luminosity Edot = 3.4 x 10^{36} erg s^{-1}. The pulsar is also coincident with the ASCA source AX J2021.1+3651. The implied luminosity of the associated X-ray source suggests the X-ray emission is dominated by a pulsar wind nebula unresolved by ASCA. The pulsar's unexpectedly high dispersion measure DM = 371 pc cm^{-3} and the d > 10kpc DM distance pose a new question: is PSR J2021+3651 an extremely efficient gamma-ray pulsar at the edge of the Galaxy? This is a question for AGILE and GLAST to answer.

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BibTeXRIS

Mallory S. E. Roberts, Jason W. T. Hessels, Scott M. Ransom, Victoria M. Kaspi, Paulo C. C. Freire, Fronefield Crawford, Duncan R. Lorimer. 2004-02-08. PSR J2021+3651: A New Gamma-Ray Pulsar Candidate. https://doi.org/10.1016/j.asr.2003.04.021

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