L. Guillemot, M. Kramer, T. J. Johnson, H. A. Craig, R. W. Romani, C. Venter, A. K. Harding, R. D. Ferdman, I. H. Stairs, M. Kerr
We report the Fermi Large Area Telescope discovery of gamma-ray pulsations from the 22.7-ms pulsar A in the double pulsar system J0737-3039A/B. This is the first mildly recycled millisecond pulsar (MSP) detected in the GeV domain. The 2.7-s companion object PSR J0737-3039B is not detected in gamma rays. PSR J0737-3039A is a faint gamma-ray emitter, so that its spectral properties are only weakly constrained; however, its measured efficiency is typical of other MSPs. The two peaks of the gamma-ray light curve are separated by roughly half a rotation and are well offset from the radio and X-ray emission, suggesting that the GeV radiation originates in a distinct part of the magnetosphere from the other types of emission. From the modeling of the radio and the gamma-ray emission profiles and the analysis of radio polarization data, we constrain the magnetic inclination $\alpha$ and the viewing angle $\zeta$ to be close to 90$^\circ$, which is consistent with independent studies of the radio emission from PSR J0737-3039A. A small misalignment angle between the pulsar's spin axis and the system's orbital axis is therefore favored, supporting the hypothesis that pulsar B was formed in a nearly symmetric supernova explosion.
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http://arxiv.org/abs/1303.7352
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