Brian Humensky, Columbia University

Date: 
Mon, 10/15/2018 - 4:15pm
Location: 
428 Pupin Hall

 

"Particle Accelerators in Space: An Air-Cherenkov Telescope’s View"

Our universe carries a small but important population of highly energetic denizens, including supernova remnants with fast shocks, and relativistic jets launched by stellar mergers and collapses, as well as by supermassive black holes. All of these environments conspire to generate populations of nonthermal particles, and observations of the very high energy (VHE; E > 100 GeV) gamma rays produced by these particles are gradually revealing the methods by which Nature accelerates cosmic rays, as well as the ways in which those cosmic rays escape and diffuse into the interstellar medium. Telescopes like VERITAS, employing the imaging air Cherenkov telescope technique, bring a unique and invaluable combination of angular resolution, energy resolution, and effective area to these observations. Recent work includes studies of cosmic-ray acceleration in the supernova remnants Cassiopeia A and IC 443, as well as the collective effects of many accelerators in the starburst galaxy M82. Meanwhile, the direct detection for the first time of gravitational wave transients by Advanced LIGO and the emergence of neutrino astronomy are providing new tools with which to probe the nature and environments of cosmic accelerators. In this talk, we discuss the impact VERITAS has had on our understanding of Galactic and cosmic accelerators, as well as status and plans for the next generation of imaging air Cherenkov telescopes, the Cherenkov Telescope Array (CTA). This work includes a novel, 9.7-m diameter prototype for CTA utilizing the Schwarzschild-Couder optical design that is currently being commissioned at the VERITAS site.

About the speaker

Brian Humensky's research activity is in the area of gamma-ray astrophysics and works on VERITAS, the Very Energetic Radiation Imaging Telescope Array System, and CTA, the Cherenkov Telescope Array (a next-generation instrument). Brian collaborates closely with fellow VERITAS and CTA member Reshmi Mukherjee.

More details on Brian's research can be found here.