When Outliers are Different

by Prof. Jonathan Katz

Washington University in St. Louis

at Astrophysics and Cosmology Seminar

Wed, 11 May 2022, 11:10
Sacta-Rashi Building for Physics (54), room 207

Abstract

Many distributions of parameters of astronomical objects contain
a single event that appears to be more extreme (more energetic, greater
value of some other parameter) than other members of that class. When can
be conclude that the most extreme object is qualitatively different? I
suggest examining the ratio of the most extreme parameter to the second-
most extreme. If the intrinisic distribution is a power law, it is possible
estimate the confidence with which the hypothesis that all are members of a
single power law distribution can be rejected. This hypothesis can be
rejected with confidence only for two such parameters: the outburst energy
of apparently non-repeating FRB and the outbursts of SGR from a single
source. This supports the hypothesis that SGR ("magnetars") are the sources
of apparently non-repeating FRB, but not the hypothesis that they are the
sources of repeating FRB.

Created on 08-05-2022 by Zitrin, Adi (zitrin)
Updaded on 08-05-2022 by Zitrin, Adi (zitrin)