Johnson, T.J.Venter, C.Guillemot, L.Kerr, M.Cognard, I.Fermi LAT2014-05-022014-05-022013Johnson, T.J. et al. 2013. Broadband pulsations from PSR B1821-24: implications for emission models and the pulsar population of M28. Astrophysical journal, 778(2): Article no 106. [https://doi.org/10.1088/0004-637X/778/2/106]0004-637X1538-4357 (Online)http://hdl.handle.net/10394/10478https://doi.org/10.1088/0004-637X/778/2/106http://iopscience.iop.org/0004-637X/778/2/106/pdf/0004-637X_778_2_106.pdfWe report the Fermi Large Area Telescope discovery of γ-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 γ rays. PSR J0737−3039A is a faint γ-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 γ-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 γ-ray emission profiles and the analysis of radio polarization data, we constrain the magnetic inclination α and the viewing angle ζ to be close to 90°, 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 as has been discussed in the literature already.en© 2013. The American Astronomical Society. All rights reserved.Gamma rays: starsGlobular clusters: individual (M28)Pulsars: individual (B1821-24)Article