Observation of polarized stochastic gravitational-wave background in pulsar-timing-array experiments

TL;DR

This paper develops a new numerical framework to detect and analyze polarized stochastic gravitational-wave backgrounds using pulsar-timing-array data, including the first calculation of linear polarization overlap reduction functions.

Contribution

It introduces a numerical scheme for computing overlap reduction functions for high multipole moments and derives the first-ever ORFs for linear polarization in SGWB.

Findings

Formulated the pulsar timing residual as a line-of-sight integral.

Constructed correlation functions using overlap reduction functions.

Provided the first calculations of linear polarization ORFs.

Abstract

We study the observation of polarized stochastic gravitational-wave background (SGWB) in pulsar-timing-array experiments. The time residual for an observed pulsar is formulated as a line-of-sight integral that incorporates the effects of the pulsar term, from which we construct the correlation function of the time residual between a pair of pulsars in terms of the overlap reduction functions (ORFs) for the SGWB intensity and polarization anisotropies. Our formulation provides a numerical scheme for computing the ORFs for high multipole moments and the lowest-moment ORFs for the SGWB linear polarization are worked out for the first time.