Joint Astrophysics Colloquium

Gamma-Ray Pulsars in the Light of New Fermi Discoveries

Alice Harding

NASA/GSFC

Pulsar studies got a major boost after the launch in June, 2008 of the Fermi Gamma-Ray Space Telescope. Almost as soon as Fermi was turned on, new gamma-ray pulsar discoveries began and a year later the number of known gamma-ray pulsars had increased by nearly a factor of ten. A large fraction of these have been discovered through their gamma-ray pulsations alone. For the first time, millisecond pulsars have been confirmed as powerful sources of gamma-ray emission, and a whole population of these objects is seen with the Fermi. From these new discoveries, we have learned that the gamma rays are not emitted in narrow lighthouse beams from near the neutron star, but in very large fan beams from the outer magnetosphere that can be seen from virtually all directions. I will discuss how Fermi is revolutionizing our understanding of pulsar physics.