Colloquium Abstract - Harding - 2025May09

May 9, 2025

11:00am Mountain

Alice Harding (LANL)

 

Pulsars in the High-Energy Sky

 

Abstract

Of the several thousand pulsars that have been discovered by radio telescopes over the past fifty years, only a handful were known to emit gamma-ray pulsations before the launch in June, 2008 of the Fermi Gamma-Ray Space Telescope. After 17 years of operation, over 300 gamma-ray pulsars have been detected and a new population of radio-quiet pulsars has been discovered. Millisecond pulsars have been confirmed as powerful sources of gamma-ray emission, and a whole population of these objects is seen with Fermi both in the Galactic plane and in globular clusters. A gamma-ray pulsar timing array (PTA) using millisecond pulsars is now operating and may soon independently detect the gravitational wave background recently discovered by radio PTAs. Fermi has thus revolutionized the study of pulsars and allowed us to peer deeper into the inner workings of these incredibly efficient natural particle accelerators. These discoveries, together with recent progress in global simulation of pulsar magnetospheres, are changing our models of pulsar particle acceleration and high-energy as well as coherent radio emission..


Local Host: Dale Frail

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