A Detection of Red Noise in PSR J1824$-$2452A and Projections for PSR B1937+21 using NICER X-ray Timing Data

Abstract

We have used X-ray data from the Neutron Star Interior Composition Explorer (NICER) to search for long time-scale, correlated variations ("red noise") in the pulse times of arrival from the millisecond pulsars PSR J1824$-$2452A and PSR B1937+21. These data more closely track intrinsic noise because X-rays are unaffected by the radio-frequency dependent propagation effects of the interstellar medium. Our Bayesian search methodology yields strong evidence (natural log Bayes factor of $9.634\pm 0.016$) for red noise in PSR J1824$-$2452A, but is inconclusive for PSR B1937+21. In the interest of future X-ray missions, we devise and implement a method to simulate longer and higher precision X-ray datasets to determine the timing baseline necessary to detect red noise. We find that the red noise in PSR B1937+21 can be reliably detected in a 5-year mission with a time-of-arrival (TOA) error of 2 microseconds and an observing cadence of 20 observations per month compared to the 5 microsecond TOA error and 11 observations per month that NICER currently achieves in PSR B1937+21. We investigate detecting red noise in PSR B1937+21 with other combinations of observing cadences and TOA errors. We also find that an injected stochastic gravitational wave background (GWB) with an amplitude of $A_{\mathrm{GWB}}=2\times 10^{-15}$ and spectral index of ${\gamma }_{\mathrm{GWB}}=13/3$ can be detected in a pulsar with similar TOA precision to PSR B1937+21, but with no additional red noise, in a 10-year mission that observes the pulsar 15 times per month and has an average TOA error of 1 microsecond.

arXiv comment21 pages, 13 figures

References in corpus (38)

• dynesty: A Dynamic Nested Sampling Package for Estimating Bayesian Posteriors and Evidences
• TEMPO2, a new pulsar timing package. I: Overview
• The international pulsar timing array project: using pulsars as a gravitational wave detector
• The NANOGrav 11-year Data Set: High-precision timing of 45 Millisecond Pulsars
• Switched magnetospheric regulation of pulsar spin-down
• Detection methods for stochastic gravitational-wave backgrounds: a unified treatment
• The NANOGrav 11-year Data Set: Pulsar-timing Constraints On The Stochastic Gravitational-wave Background
• Limits on the Stochastic Gravitational Wave Background from the North American Nanohertz Observatory for Gravitational Waves
• On the evidence for a common-spectrum process in the search for the nanohertz gravitational-wave background with the Parkes Pulsar Timing Array
• The NANOGrav Nine-year Data Set: Limits on the Isotropic Stochastic Gravitational Wave Background
• The International Pulsar Timing Array: Second data release
• PINT: A Modern Software Package for Pulsar Timing
• Pulsar timing analysis in the presence of correlated noise
• Understanding and analysing time-correlated stochastic signals in pulsar timing
• NANOGrav Limits on Gravitational Waves from Individual Supermassive Black Hole Binaries in Circular Orbits
• Hyper-efficient model-independent Bayesian method for the analysis of pulsar timing data
• From Spin Noise to Systematics: Stochastic Processes in the First International Pulsar Timing Array Data Release
• Frequency-Dependent Dispersion Measures and Implications for Pulsar Timing
• The NANOGrav 12.5-year Data Set: Wideband Timing of 47 Millisecond Pulsars
• Pulsar Braking Indices Revisited
• Identifying and mitigating noise sources in precision pulsar timing data sets
• Time-domain Implementation of the Optimal Cross-Correlation Statistic for Stochastic Gravitational-Wave Background Searches in Pulsar Timing Data
• An Asteroid Belt Interpretation for the Timing Variations of the Millisecond Pulsar B1937+21
• The NANOGrav Nine-Year Data Set: Excess Noise in Millisecond Pulsar Arrival Times
• Realistic sensitivity curves for pulsar timing arrays
• Pulsar timing noise from superfluid turbulence
• Bayesian model selection without evidences: application to the dark energy equation-of-state
• Timing Gamma-ray Pulsars with the Fermi Large Area Telescope: Timing Noise and Astrometry
• The NANOGrav Nine-Year Data Set: Noise Budget for Pulsar Arrival Times on Intraday Timescales
• Low-rank approximations for large stationary covariance matrices, as used in the Bayesian and generalized-least-squares analysis of pulsar-timing data
• Modelling and mitigating refractive propagation effects in precision pulsar timing observations
• The NANOGrav 11-Year Data Set: Evolution of Gravitational Wave Background Statistics
• High-Precision X-ray Timing of Three Millisecond Pulsars with NICER: Stability Estimates and Comparison with Radio
• Effects of the ISM on Detection of Low-frequency Gravitational Waves
• Bayesian estimation of non-Gaussianity in pulsar timing analysis
• Minimum Requirements for Detecting a Stochastic Gravitational Wave Background Using Pulsars
• High precision pulsar timing and spin frequency second derivatives
• OH Evolution in Molecular Clouds

Cited by in corpus (1)

• Intra-pulse variability induced by plasmoid formation in pulsar magnetospheres