Title: A NonRadial Oscillation Model for Radio Pulsars
1A Non-Radial Oscillation Model for Radio Pulsars
In collaboration with Dr. J. Christopher
Clemens University of North Carolina at Chapel
Hill
2Average Pulse Shapes
3Polarization Properties
Stinebring, D. R., Cordes, J. M., Rankin, J. M.,
Weisberg, J. M., Boriakoff, V. 1984, ApJS, 55,
247
4Drifting Subpulses
5Vacuum Gap, Drifting Spark Model
6Phase Shifts
PSR 032039
Rapidly oscillating Ap star HR 3831
Edwards, R. T., Stappers, B. W., van Leeuwen,
A. G. J. 2003, AA, 401, 321
7Intensity and Velocity Variations
The displacement (intensity) variations are
described as
The velocity variations are described as
Where are spherical coordinates
aligned to the magnetic axis of the star
8Intensity Variations in WDs
l 2, m 0
l 1, m 0
9Polarization Geometry
Displacements and velocities are aligned to
magnetic pole Induced electric field (E?) due
to E? v x B(0) is orthogonal to E? Result two
orthogonal electric fields
10Our Model
11Single Pulse Behavior
12PSR 094310 Data
The
Single pulses
Fourier Transform
13PSR 094310 Dual Frequencies
Two possibilities for a split subpulse
frequency 1. Two closely spaced independent
frequencies 2. Combined frequency and amplitude
or phase modulation of a single frequency
14PSR B094310
Pulsational and geometrical parameters are
largely independent
15Conclusions and Future Work
- Developed a physical model for pulsar morphology
based on asteroseismological principles - Conducted quantitative fitting of model to data
- Next step fit more complex pulsar behavior,
acquire data for definitive tests - Subpulse phase correlation between both magnetic
poles - Subpulse frequency independent of observational
radio frequency