Single Epoch Measurements of Dispersion Measure Gradients Towards PSR B0834+06

Abstract

Understanding the evolution of pulsar dispersion measures is vital to high precision timing experiments, as well as astrometric experiments to determine pulsar positions and proper motions. In this work, we present a novel approach to measuring dispersion measure gradients using pulsar scintillometry. This approach makes use of the multipath propagation through the interstellar medium to simultaneously probe dispersion measures along multiple sight lines from a single observation. Using existing data of PSR B0834+06, we are able to measure gradients of $9.7\pm0.3\times10^{-6}~\rm{pc}~\rm{cm}^{-3}~\rm{mas}^{-1}$.