A Quantitative Model for Drifting Subpulses in PSR B0809+74

TL;DR

This study analyzes high-resolution single pulse data of PSR B0809+74 at 820 MHz, revealing complex subpulse behaviors, phase jumps, and polarization correlations, and demonstrates that a non-radial oscillation model can accurately explain these phenomena.

Contribution

It introduces a quantitative fit of the subpulse behavior using a non-radial oscillation model, challenging traditional drifting spark models.

Findings

Subpulse period varies over time.

Subpulse phase jump ranges from 95 to 147 degrees.

Non-radial oscillation model reproduces observed behaviors.

Abstract

In this paper we analyze high time resolution single pulse data of PSR B0809+74 at 820 MHz. We compare the subpulse phase behavior, undocumented at 820 MHz, with previously published results. The subpulse period changes over time and we measure a subpulse phase jump, when visible, that ranges from 95 to 147 degrees. We find a correlation between the subpulse modulation, subpulse phase, and orthogonal polarization modes. This variety of complicated behavior is not well understood and is not easily explained within the framework of existing models, most of which are founded on the drifting spark model of Ruderman & Sutherland (1975). We quantitatively fit our data with a non-radial oscillation model (Clemens & Rosen 2008) and show that the model can accurately reproduce the drifting subpulses, orthogonal polarization modes, subpulse phase jump, and can explain the correlation between all these features.