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arXiv · 0806.1200

PSR J1856+0245: Arecibo Discovery of a Young, Energetic Pulsar Coincident with the TeV Gamma-ray Source HESS J1857+026

J. W. T. Hessels·D. J. Nice·B. M. Gaensler·V. M. Kaspi·D. R. Lorimer·D. J. Champion·A. G. Lyne·M. Kramer·J. M. Cordes·P. C. C. Freire·F. Camilo·S. M. Ransom·J. S. Deneva·N. D. R. Bhat·I. Cognard·F. Crawford·F. A. Jenet·L. Kasian·P. Lazarus·J. van Leeuwen·M. A. McLaughlin·I. H. Stairs·B. W. Stappers·A. Venkataraman
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Abstract

We present the discovery of the Vela-like radio pulsar J1856+0245 in the Arecibo PALFA survey. PSR J1856+0245 has a spin period of 81ms, a characteristic age of 21kyr, and a spin-down luminosity Edot = 4.6 x 10^36 ergs/s. It is positionally coincident with the TeV gamma-ray source HESS J1857+026, which has no other known counterparts. Young, energetic pulsars create wind nebulae, and more than a dozen pulsar wind nebulae have been associated with very-high-energy (100GeV-100TeV) gamma-ray sources discovered with the HESS telescope. The gamma-ray emission seen from HESS J1857+026 is potentially produced by a pulsar wind nebula powered by PSR J1856+0245; faint X-ray emission detected by ASCA at the pulsar's position supports this hypothesis. The inferred gamma-ray efficiency is epsilon_gamma = L_gamma/Edot = 3.1% (1-10TeV, for a distance of 9kpc), comparable to that observed in similar associations.

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J. W. T. Hessels, D. J. Nice, B. M. Gaensler, V. M. Kaspi, D. R. Lorimer, D. J. Champion, A. G. Lyne, M. Kramer, J. M. Cordes, P. C. C. Freire, F. Camilo, S. M. Ransom, J. S. Deneva, N. D. R. Bhat, I. Cognard, F. Crawford, F. A. Jenet, L. Kasian, P. Lazarus, J. van Leeuwen, M. A. McLaughlin, I. H. Stairs, B. W. Stappers, A. Venkataraman. 2008-06-06. PSR J1856+0245: Arecibo Discovery of a Young, Energetic Pulsar Coincident with the TeV Gamma-ray Source HESS J1857+026. https://doi.org/10.1086/590908

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