The 2009 Fermi Symposium

Precise Pulsar Timing and Radio Follow-Up of Pulsars Discovered in LAT Blind Periodicity Searches

Paul Ray, Naval Research Laboratory

Abstract:

Blind periodicity searches with the Fermi LAT have been highly successful, with at least 16 discoveries reported so far (Abdo et al. 2009). These gamma-ray selected pulsars are a very important subset of the gamma-ray pulsars detected by the LAT, since they are potentially radio-quiet pulsars like Geminga and are subject to very different selection effects than the known population of radio pulsars. We describe the gamma-ray pulse timing measurements of these pulsars, from which positions can be measured at the few arcsecond level. These positions, far more precise than positions derived from LAT photon direction measurements, are critical for multi-wavelength follow up. We have made deep radio observations of the new gamma-ray selected pulsars to search for radio pulsations. When successful, radio observations can provide measurements of the distance to the pulsar and the emission geometry. Strong upper limits contribute to population statistics that constrain the emission models for the sources. In this talk, I describe the results of the pulse timing measurements and the current status of the radio pulsation searches.