Finding More & More Gamma-ray Pulsars with the Fermi LAT


Over 300 pulsars are seen to pulse in GeV gamma rays acquired with the Large Area Telescope (LAT) on the Fermi satellite.
Many more may be waiting for discovery: of the >2000 LAT sources with no counterpart known at other wavelengths, hundreds are non-variable, with pulsar-like spectral shapes and sky distributions.
In addition, population syntheses typically predict as many as twice the current LAT pulsar sample.
However, detecting gamma-ray pulsations will be difficult for most of the new ones, whether through blind searches of the gamma-ray data, or using long-term phase-connected rotation ephemeredes for radio pulsars.

I will describe the sample of gamma-ray pulsars in the 3rd LAT Pulsar Catalog, and the ongoing work to transform candidates into discoveries. I will focus on the opportunities that FAST provides to identify the radio-faint,
gamma-loud pulsars hidden in the LAT data, highlighting some of the science that further discoveries enable.



Speaker: 
David Smith（French National Center for Scientific Research）
Place: 
KIAA-auditorium
Host: 
Kejia Lee
Time: 
Tuesday, December 3, 2024 - 3:30PM to Tuesday, December 3, 2024 - 4:30PM
Biography: 
David A. Smith works with NASA’s Fermi satellite at the Laboratoire d’Astrophysique de Bordeaux, a laboratory of the French National Center for Scientific Research (CNRS). The Large Area Telescope (LAT), Fermi’s primary instrument, is sensitive to gamma-ray photons in the GeV energy range. Fermi was called GLAST before being launched from Cape Canaveral in June, 2008. Smith grew up in Berkeley, California, and obtained a B.A. in Physics from the University there. He received his PhD from the University of Illinois at Urbana-Champaign in 1988, for work on the CDF experiment at the Fermilab proton-antiproton collider that contributed to the discovery of the Top quark. He was part of a small team that built and commissioned the then-largest muon detector in the world, specializing in the front-end and trigger electronics. He was a postdoctoral fellow at the National Institute for Nuclear Physics (INFN) in Pisa, Italy for six years. David Smith switched to gamma ray astrophysics in 1991, developing innovative telescopes to exploit atmospheric Cherenkov light. He worked on experiments on the island of La Palma in the Canaries, and led the reconversion of a solar facility in the French Pyrenees into a gamma-ray telescope, focussing on the data acquisition electronics. He joined the CNRS staff in 1995. The Bordeaux group discovered of a large number of gamma-ray pulsars, widely published. Smith organised an international consortium to time pulsar rotations using radio telescopes around the world. Smith also led the testing of Fermi’s GPS-based precision clocks. His primary research interest is the study of gamma-ray pulsars. He also explores the nature of the approximately 2000 GeV LAT sources with no presently known counterpart at other wavelengths. To this end, he has been looking into massive star formation regions (SFRs) as gamma-ray emitters since late 2023.