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arXiv · 1207.5333

PSR J1838-0537: Discovery of a young, energetic gamma-ray pulsar

H. J. Pletsch·L. Guillemot·B. Allen·M. Kramer·C. Aulbert·H. Fehrmann·M. G. Baring·F. Camilo·P. A. Caraveo·J. E. Grove·M. Kerr·M. Marelli·S. M. Ransom·P. S. Ray·P. M. Saz Parkinson
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Abstract

We report the discovery of PSR J1838-0537, a gamma-ray pulsar found through a blind search of data from the Fermi Large Area Telescope (LAT). The pulsar has a spin frequency of 6.9 Hz and a frequency derivative of -2.2e-11 Hz/s, implying a young characteristic age of 4970 years and a large spin-down power of 5.9e36 erg/s. Follow-up observations with radio telescopes detected no pulsations, thus PSR J1838-0537 appears radio-quiet as viewed from Earth. In September 2009 the pulsar suffered the largest glitch so far seen in any gamma-ray-only pulsar, causing a relative increase in spin frequency of about 5.5e-6. After the glitch, during a putative recovery period, the timing analysis is complicated by the sparsity of the LAT photon data, the weakness of the pulsations, and the reduction in average exposure from a coincidental, contemporaneous change in the LAT's sky-survey observing pattern. The pulsar's sky position is coincident with the spatially extended TeV source HESS J1841-055 detected by the High Energy Stereoscopic System (H.E.S.S.). The inferred energetics suggest that HESS J1841-055 contains a pulsar wind nebula powered by the pulsar.

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H. J. Pletsch, L. Guillemot, B. Allen, M. Kramer, C. Aulbert, H. Fehrmann, M. G. Baring, F. Camilo, P. A. Caraveo, J. E. Grove, M. Kerr, M. Marelli, S. M. Ransom, P. S. Ray, P. M. Saz Parkinson. 2012-07-23. PSR J1838-0537: Discovery of a young, energetic gamma-ray pulsar. https://doi.org/10.1088/2041-8205%2F755%2F1%2Fl20

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