PSR J0007+7303 in the CTA1 SNR: New Gamma-ray Results from Two Years of   Fermi-LAT Observations
  One of the main results of the Fermi Gamma-Ray Space Telescope is the discovery of {\gamma}-ray selected pulsars. The high magnetic field pulsar, PSR J0007+7303 in CTA1, was the first ever to be discovered through its {\gamma}-ray pulsations. Based on analysis of 2 years of LAT survey data, we report on the discovery of {\gamma}-ray emission in the off-pulse phase interval at the ~ 6{\sigma} level. The flux from this emission in the energy range E \geq 100 MeV is F_100 = (1.73\pm0.40)\times10^(-8) photons/cm^2/s and is best fitted by a power law with a photon index of {\Gamma} = 2.54\pm0.14. The pulsed {\gamma}-ray flux in the same energy range is F_100 = (3.95\pm0.07)\times10^(-7) photons/cm^2/s and is best fitted by an exponentially-cutoff power-law spectrum with a photon index of {\Gamma} = 1.41 \pm 0.23 and a cutoff energy E_c = 4.04 \pm 0.20 GeV. We find no flux variability neither at the 2009 May glitch nor in the long term behavior. We model the {\gamma}-ray light curve with two high-altitude emission models, the outer gap and slot gap, and find that the model that best fits the data depends strongly on the assumed origin of the off-pulse emission. Both models favor a large angle between the magnetic axis and observer line of sight, consistent with the nondetection of radio emission being a geometrical effect. Finally we discuss how the LAT results bear on the understanding of the cooling of this neutron star. 
A. A. Abdo, K. S. Wood, M. E. DeCesar, F. Gargano, F. Giordano, P. S.   Ray, D. Parent, A. K. Harding, M. Coleman Miller, D....
astro-ph.HE astro-ph.IM