Tracking dispersion measure variations of timing array pulsars with the GMRT

Ujjwal Kumar; Yashwant Gupta; Willem van Straten; Stefan Oslowski; Jayanta Roy; N. D. R. Bhat; Matthew Bailes; Michael J. Keith

doi:10.1017/s1743921312024404

arXiv · 1210.5358

Tracking dispersion measure variations of timing array pulsars with the GMRT

Ujjwal Kumar·Yashwant Gupta·Willem van Straten·Stefan Oslowski·Jayanta Roy·N. D. R. Bhat·Matthew Bailes·Michael J. Keith

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Abstract

We present the results from nearly three years of monitoring of the variations in dispersion measure (DM) along the line-of-sight to 11 millisecond pulsars using the Giant Metrewave Radio Telescope (GMRT). These results demonstrate accuracies of single epoch DM estimates of the order of 5x10^(-4) cm^(-3) pc. A preliminary comparison with the Parkes Pulsar Timing Array (PPTA) data shows that the measured DM fluctuations are comparable. We show effects of DM variations due to the solar wind and solar corona and compare with the existing models.

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Ujjwal Kumar, Yashwant Gupta, Willem van Straten, Stefan Oslowski, Jayanta Roy, N. D. R. Bhat, Matthew Bailes, Michael J. Keith. 2012-10-19. Tracking dispersion measure variations of timing array pulsars with the GMRT. https://doi.org/10.1017/s1743921312024404

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