SCHOOL OF STATISTICS

and

THE COLLEGE OF LIBERAL ARTS

UNIVERSITY OF MINNESOTA

 

BUEHLER-MARTIN DISTINGUISHED LECTURER SERIES

April 12, 14 and 15, 2010

 

Established by Mr. and Mrs. Thomas Martin

in Memory of

Robert J. Buehler, Professor of Statistics (1963-1988)

 

John Rice

Department of Statistics

University of California, Berkeley

 

Searching for Gamma-Ray Pulsars: Detecting Periodicity in a Point Process

 

Thursday, April 15, 2010    3:30 PM

Ford Hall 115

(Refreshments: 3:00 PM, Ford Hall 300)

 

I will discuss a statistical problem that arises in astronomy: detecting gamma-ray pulsars. The problem can be formulated as that of detecting periodicity in the rate function of a point process or a marked point process when the periodic function cannot be specified in parametric form and the frequency may decay. I will briefly discuss the scientific background and then present a class of detection procedures, weighted quadratic test statistics arising from a score test,  that take into account auxiliary information such as source intensity, background intensity, and incidence angles and energies associated with each photon arrival.

There are very substantial computational demands, since searching over a range of frequency and frequency drift can be a daunting task, even for a record consisting of only a thousand or so events.  I will discuss a method that maximizes power subject to a computational constraint.