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arXiv · 1911.04934

Observed glitches in 8 young pulsars

Avishek Basu·Bhal Chandra Joshi·M. A. Krishnakumar·Dipankar Bhattacharya·Rana Nandi·Debades Bandyopadhyay·Prasanta Char·P. K. Manoharan
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Abstract

The abrupt change in the pulse period of a pulsar is called a pulsar glitch. In this paper, we present eleven pulsar glitches detected using the Ooty Radio Telescope (ORT) and the upgraded Giant Metrewave Radio Telescope (uGMRT) in high cadence timing observations of 8 pulsars. The measured relative amplitude of glitches ($Δν/ν$) from our data ranges from $10^{-6}$ to $10^{-9}$. Among these glitches, three are new discoveries, being reported for the first time. We also reanalyze the largest pulsar glitch in the Crab pulsar (PSR J0534+2200) by fitting the ORT data to a new phenomenological model including the slow rise in the post-glitch evolution. We measure an exponential recovery of 30 days after the Vela glitch detected on MJD 57734 with a healing factor $Q=5.8\times 10^{-3}$. Further, we report the largest glitch ($Δν/ν= 3147.9 \times 10^{-9}$) so far in PSR J1731$-$4744.

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Avishek Basu, Bhal Chandra Joshi, M. A. Krishnakumar, Dipankar Bhattacharya, Rana Nandi, Debades Bandyopadhyay, Prasanta Char, P. K. Manoharan. 2019-12-18. Observed glitches in 8 young pulsars. https://doi.org/10.1093/mnras%2Fstz3230

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