Generalized optimal statistic for characterizing multiple correlated signals in pulsar timing arrays

Abstract

The optimal statistic (OS) is a frequentist estimator for the amplitude and significance of a spatially-correlated signal in pulsar timing array (PTA) data, and it is widely used to search for the gravitational wave background (GWB). However, the OS cannot perfectly distinguish between different spatial correlations. In this paper, we introduce the multiple component optimal statistic (MCOS): a generalization of the OS that allows for multiple correlations to be simultaneously fit to the data. We use simulated data to show that this method more accurately recovers injected spatially correlated signals, and in particular reduces the risk of a false detection of a signal with the wrong spatial correlation. We also demonstrate that this method can be used to recover multiple correlated signals.

arXiv comment11 pages, 9 figures, 4 tables

References in corpus (26)

• The NANOGrav 12.5-year Data Set: Search For An Isotropic Stochastic Gravitational-Wave Background
• High-precision timing of 42 millisecond pulsars with the European Pulsar Timing Array
• Limits on the Stochastic Gravitational Wave Background from the North American Nanohertz Observatory for Gravitational Waves
• Low-frequency gravitational radiation from coalescing massive black hole binaries in hierarchical cosmologies
• The International Pulsar Timing Array: Second data release
• The Astrophysics of Nanohertz Gravitational Waves
• Optimal strategies for gravitational wave stochastic background searches in pulsar timing data
• The stochastic background: scaling laws and time to detection for pulsar timing arrays
• Development of a pulsar-based timescale
• The NANOGrav 12.5 yr Data Set: Observations and Narrowband Timing of 47 Millisecond Pulsars
• Stochastic backgrounds in alternative theories of gravity: overlap reduction functions for pulsar timing arrays
• Mapping gravitational-wave backgrounds using methods from CMB analysis: Application to pulsar timing arrays
• A study of spatial correlations in pulsar timing array data
• Time-domain Implementation of the Optimal Cross-Correlation Statistic for Stochastic Gravitational-Wave Background Searches in Pulsar Timing Data
• A pulsar-based timescale from the International Pulsar Timing Array
• Modeling the uncertainties of solar-system ephemerides for robust gravitational-wave searches with pulsar timing arrays
• The Indian Pulsar Timing Array: First data release
• Towards Robust Gravitational Wave Detection with Pulsar Timing Arrays
• Noise-marginalized optimal statistic: A robust hybrid frequentist-Bayesian statistic for the stochastic gravitational-wave background in pulsar timing arrays
• Hellings and Downs correlation of an arbitrary set of pulsars
• Mapping gravitational-wave backgrounds in modified theories of gravity using pulsar timing arrays
• The NANOGrav 12.5-year data set: Search for Non-Einsteinian Polarization Modes in theGravitational-Wave Background
• Gravitational wave emission from binary supermassive black holes
• Constraining alternative theories of gravity using pulsar timing arrays
• Forecasting pulsar timing array sensitivity to anisotropy in the stochastic gravitational wave background
• Ephemeris Errors and the Gravitational Wave Signal: Harmonic Mode Coupling in Pulsar Timing Array Searches

Cited by in corpus (7)

• The NANOGrav 15-year Gravitational-Wave Background Methods
• Pulsar Timing Arrays require hierarchical models
• Spatial and Spectral Characterization of the Gravitational-wave Background with the PTA Optimal Statistic
• Systematic errors in searches for nanohertz gravitational waves
• The NANOGrav 15 yr data set: Posterior predictive checks for gravitational-wave detection with pulsar timing arrays
• Rapid Construction of Joint Pulsar Timing Array Datasets: The Lite Method
• On the calculation of p-values for quadratic statistics in Pulsar Timing Arrays