A new code for parameter estimation in searches for gravitational waves from known pulsars

TL;DR

This paper introduces a new nested sampling-based code for estimating gravitational wave parameters from known pulsars, improving efficiency and accuracy over previous methods using grid and MCMC techniques.

Contribution

The paper presents a novel parameterization of neutron star orientation angles that enhances exploration efficiency and introduces a new code for gravitational wave parameter estimation.

Findings

The new code performs consistent parameter estimation with fake signals and simulated noise.

The new angle parameterization breaks degeneracies, improving exploration.

Comparison shows improved efficiency over previous grid and MCMC methods.

Abstract

We describe the consistency testing of a new code for gravitational wave signal parameter estimation in known pulsar searches. The code uses an implementation of nested sampling to explore the likelihood volume. Using fake signals and simulated noise we compare this to a previous code that calculated the signal parameter posterior distributions on both a grid and using a crude Markov chain Monte Carlo (MCMC) method. We define a new parameterisation of two orientation angles of neutron stars used in the signal model (the initial phase and polarisation angle), which breaks a degeneracy between them and allows more efficient exploration of those parameters. Finally, we briefly describe potential areas for further study and the uses of this code in the future.