David Smith — Faint Gamma-ray Pulsars

Quand :
3 octobre 2018 @ 11 h 00 min – 12 h 00 min
Où :
Univers 21

In its 11th year on orbit, the Fermi LAT continues to discover GeV gamma-rays from
about 24 pulsars per year. The most sensitive way to find them is to use rotation ephemerides
to « phase fold » the gamma photons, to then look whether the resulting
phase histogram is flat or not. We have done this for over a thousand radio pulsars,
using ephemerides provided by the Nancay, Jodrell Bank, and Parkes radio telescopes.
I will present sixteen gamma-ray pulsars we found, and explain how they enhance the sample
of over 220 pulsars we already had. I will discuss possible causes of the gamma-ray
« deathline » near a spindown power of Edot ~ few 1E33 erg/s.
Finally, I will say some words about extrapolating the observed gamma-ray pulsar
population to estimate the contribution of unresolved pulsars to the diffuse background.