"Fast radio bursts from across the Universe?" by Vikram Ravi (Caltech)

Thursday, October 20, 2016 - 4:00pm to 5:00pm
Physics and Astronomy Colloquium

Thursdays, 4:00-5:00 pm

1-434 Physics and Astronomy (map)
Reception from 3:30-4:00 p.m.
(unless otherwise posted)


Guest Speaker: Vikram Ravi (California Institute of Technology)

Talk Title:  “Fast radio bursts from across the Universe?”


On timescales of microseconds to seconds, the Gigahertz radio sky bristles with activity. For almost 50 years, bursts of emission on these timescales have been associated with neutron stars within the Milky Way. Recently, however, time-domain radio surveys have revealed a new population of astrophysical fast (millisecond) radio bursts (FRBs), with peak flux densities that rival the brightest quasars. Their cold-plasma dispersion delays, and levels of pulse-broadening due to multi-path propagation, are significantly in excess of expectations from the Milky Way along their sightlines. They are thus identified as coherent outbursts from extragalactic compact objects. This, however, remains the extent of our knowledge. We do not know from which objects in which galaxies, and at what distances, they originate. I will discuss possible insights into these basic properties from analyses of observed FRBs, and provide updates on a selection of FRB localization efforts.  In addition to representing a new, likely exotic form of radio source, FRBs provide the opportunity for tomographic studies of the density, turbulence, and magnetization of plasma in the interstellar media of distant galaxies, in galactic halos, and in the intergalactic medium.


For more information, contact Jay Hauser

We thank the following people for their contributions to the wine fund for the post-colloquium reception:
Prof. Dolores Bozovic, Prof. Mike Cornwall, Prof. Bob Cousins, Prof. Andrea Ghez, Prof. Karoly Holczer, Prof. Eric Hudson, Robert Huff, Prof. Alex Kusenko, Prof. Myank Mehta, Prof. John Miao, Prof. Roberto Peccei, Prof. Claudio Pellegrini, Prof. David Saltzberg, Prof. Jean Turner and Prof. Ben Zuckerman.

1-434 PAB