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arXiv · 2404.02051

The Thousand-Pulsar-Array programme on MeerKAT XIII: Timing, flux density, rotation measure and dispersion measure timeseries of 597 pulsars

M. J. Keith·S. Johnston·A. Karastergiou·P. Weltevrede·M. E. Lower·A. Basu·B. Posselt·L. S. Oswald·A. Parthasarathy·A. D. Cameron·M. Serylak·S. Buchner
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Abstract

We report here on the timing of 597 pulsars over the last four years with the MeerKAT telescope. We provide Times-of-Arrival, pulsar ephemeris files and per-epoch measurements of the flux density, dispersion measure (DM) and rotation measure (RM) for each pulsar. In addition we use a Gaussian process to model the timing residuals to measure the spin frequency derivative at each epoch. We also report the detection of 11 glitches in 9 individual pulsars. We find significant DM and RM variations in 87 and 76 pulsars respectively. We find that the DM variations scale approximately linearly with DM, which is broadly in agreement with models of the ionised interstellar medium. The observed RM variations seem largely independent of DM, which may suggest that the RM variations are dominated by variations in the interstellar magnetic field on the line of sight, rather than varying electron density. We also find that normal pulsars have around 5 times greater amplitude of DM variability compared to millisecond pulsars, and surmise that this is due to the known difference in their velocity distributions.

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M. J. Keith, S. Johnston, A. Karastergiou, P. Weltevrede, M. E. Lower, A. Basu, B. Posselt, L. S. Oswald, A. Parthasarathy, A. D. Cameron, M. Serylak, S. Buchner. 2024-04-02. The Thousand-Pulsar-Array programme on MeerKAT XIII: Timing, flux density, rotation measure and dispersion measure timeseries of 597 pulsars. https://arxiv.org/abs/2404.02051

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