Hope College Department of Physics and Engineering
Research Experiences for Undergraduates
Analyzing Two Peak Pulsar Radio Profiles to Constrain Viewing Geometry and Extract the Luminosity of the Conal Beam
|Student Name:||Sarah Story (with Ruth Arevalo and Brenna Giacherio)|
|Student's Home Institution:||Hope College|
|Research Advisor:||Dr. Peter Gonthier|
|Source of Support:||
NSF-REU, Michigan Space Grant Consortium
The intensity profiles of pulsars usually reveal one, two, or three peaks produced by radio emission from the core or cone, which are located near the polar cap. This project first focused on constraining the viewing geometry of three peak pulsars, work previously begun by Brenna Giacherio, and then moved on to that of two peak pulsars. The two peak pulsars were mainly characterized by cone emission however, a few pulsars were discovered that appeared to behave as three peak pulsars even though only two peaks were evident. Fitting the two peak profiles provided additional data to test the luminosity model Dr. Gonthier developed based on constraining the viewing geometry of three peak pulsars. Since the luminosity model did not correctly predict the luminosities perceived by the fits future work will include analyzing how well the viewing geometries were constrained and developing a more accurate luminosity model.
We express our gratitude for the generous support of the Michigan Space Grant Consortium, of Research Corporation (CC5813), of the National Science Foundation (REU-0452206 and AST-0307365) and the NASA Astrophysics Theory Program.
Results from this work have been presented at the American Astronomical Society 207th Meeting, 8-12 January 2006,
"Population statistics study of radio and gamma-ray millisecond
pulsars in the Galactic plane", Story, S.A., Gonthier, P.L., and Harding,
Astronomical Society Meeting 207, January 2005. #183.10.
"The role of core and cone beams in radio pulsar emission", Gonthier,
P.L., Story, S.A., Giacherio, B.M., Arevalo, R.A., and Harding, A.K., American
Astronomical Society Meeting 207, January 2005. #183.12.
"Developing radio beam geometry and luminosity models of pulsars", Gonthier, P.L., Story, S.A., Giacherio, B.M., Arevalo, R.A., and Harding, A.K., Chinese Journal of Astronomy and Astrophysics, 6, (2006) pp.97-104.