Hope College Department of Physics and Engineering
Research Experiences for Undergraduates
Summer 2003
Project Summary


Project Title: Beam Geometry and Luminosity Model for the Radio Emission of
Student Name: Stefan Coltisor
Studentís home institution: Hope College
Research Advisor(s): Dr. Peter Gonthier
Source of Support: Sherman Fairchild Foundation

During this project we explored a beam geometry and luminosity model for the radio emission from radio pulsars. For the first part of this project we used an IGOR Pro based program that simulated the profile intensity of a given pulsar for only one specific frequency. We experienced and learned a lot with this software. However, we also realized that a program simulating only one frequency at a time is far from sufficient for obtaining fast and reliable knowledge. Thus, during the second part of this project, I dedicated my time designing, writing and testing another version of this IGOR Pro based program capable of analyzing and interpreting data corresponding to multiple frequencies of a given pulsar at a time. Also, this program was planned to include small modification of the initial model, this modification being the fruit of our previous work using the single frequency simulation program.The program had to include a new parameterization of the conal angular width as described by Mitra & Despande (1999). We have also decided to modify the fitting process in a way that would allow us to define a new luminosity model, and determine its characteristic constants. It proved to be a rather difficult task, and so preliminary simulations and conclusions have not been possible before the end of the summer part of this research project. However, a beta version of this program has been created and we expect that once the project is resumed (at the beginning of September, 2002) final testing will allow us to finish the program and start running simulations and fittings.


I would like to conclude that this project revealed the lack of consistence of the already existing models and the necessity of a new model, that would better explain and account for the polarization and total radio intensity characteristics of pulsars. Using the newly created simulation program, we hope to provide such a model in the near future.