Effects of periodicity in observation scheduling on parameter estimation of pulsar glitches

Abstract

In certain pulsar timing experiments, where observations are scheduled approximately periodically (e.g. daily), timing models with significantly different frequencies (including but not limited to glitch models with different frequency increments) return near-equivalent timing residuals. The average scheduling aperiodicity divided by the phase error due to time-of-arrival uncertainties is a useful indicator of when the degeneracy is important. Synthetic data are used to explore the effect of this degeneracy systematically. It is found that phase-coherent tempo2 or temponest-based approaches are biased sometimes toward reporting small glitch sizes regardless of the true glitch size. Local estimates of the spin frequency alleviate this bias. A hidden Markov model is free from bias towards small glitches and announces explicitly the existence of multiple glitch solutions but sometimes fails to recover the correct glitch size. Two glitches in the UTMOST public data release are re-assessed, one in PSR J1709$-$4429 at MJD 58178 and the other in PSR J1452$-$6036 at MJD 58600. The estimated fractional frequency jump in PSR J1709$-$4429 is revised upward from $\Delta f/f=(54.6\pm 1.0)\times 10^{-9}$ to $\Delta f/f=(2432.2\pm 0.1)\times 10^{-9}$ with the aid of additional data from the Parkes radio telescope. We find that the available UTMOST data for PSR J1452$-$6036 are consistent with $\Delta f/f=270\times 10^{-9}+N/(fT)$ with $N=0,1,2$, where $T\approx 1\text{sidereal day}$ is the observation scheduling period. Data from the Parkes radio telescope can be included, and the $N=0$ case is selected unambiguously with a combined dataset.

arXiv commentAccepted for publication in MNRAS. 16 pages, 12 figures

References in corpus (23)

• MultiNest: an efficient and robust Bayesian inference tool for cosmology and particle physics
• TEMPO2, a new pulsar timing package. I: Overview
• Tempo2, a new pulsar timing package. II: The timing model and precision estimates
• A study of 315 glitches in the rotation of 102 pulsars
• Detection of 107 glitches in 36 southern pulsars
• TempoNest: A Bayesian approach to pulsar timing analysis
• High time resolution observations of the January 2000 glitch in the Vela pulsar
• Observations of a Series of Six Recent Glitches in the Crab Pulsar
• The Parkes Observatory Pulsar Data Archive
• The UTMOST pulsar timing programme II: Timing noise across the pulsar population
• 30 Glitches in slow pulsars
• The UTMOST: A hybrid digital signal processor transforms the MOST
• The UTMOST pulsar timing programme I: overview and first results
• Timing of young radio pulsars II. Braking indices and their interpretation
• Neutron star glitches have a substantial minimum size
• Pulsar glitch detection with a hidden Markov model
• Pulsar science with the CHIME telescope
• Characterising the rotational irregularities of the Vela pulsar from 21 yr of phase-coherent timing
• Observed glitches in 8 young pulsars
• On the detection probability of neutron star glitches
• Detection of a glitch in the pulsar J1709-4429
• The UTMOST Survey for Magnetars, Intermittent pulsars, RRATs and FRBs I: System description and overview
• Constraints on wide-band radiative changes after a glitch in PSR J1452-6036

Cited by in corpus (4)

• Narrowband searches for continuous and long-duration transient gravitational waves from known pulsars in the LIGO-Virgo third observing run
• Systematic upper limits on the size of missing pulsar glitches in the first UTMOST open data release
• A new small glitch in Vela discovered with a hidden Markov model
• Measuring the crust-superfluid coupling time-scale for 105 UTMOST pulsars with a Kalman filter