Bias-free parameter estimation depending on sky region for targeted gravitational wave

TL;DR

This paper introduces a regularization-based method for gravitational wave parameter estimation that reduces sky-region-dependent biases, improving accuracy and enabling more precise cosmological investigations.

Contribution

The paper presents a novel a-posteriori parameter choice rule for regularization, optimizing all regulator parameters simultaneously to mitigate sky-region biases in GW parameter estimation.

Findings

Significantly shrinks credible regions in problematic sky areas.

Suppresses systematic errors related to sky-region biases.

Enhances the accuracy of amplitude parameter estimation.

Abstract

Detection of gravitational waves(GW) involves using the network of GW telescopes to observe a large sky region. However, owing to the arrangement of the GW telescopes, even with aLIGO- aVirgo-KAGRA network,parameter estimation accuracy deteriorates depending on the sky region of the GW source due to the ill-posed nature of the inverse operator. A regularization-based method is proposed herein to improve parameter estimation accuracy. Although conventional regularization methods cannot optimize all regulator parameters completely, the proposed method archives full optimization by applying an a-posteriori parameter choice rule to determine regulator parameters. We demonstrate that the proposed method can shrink the credible regions of inclination vs lumi- nosity distance and polarization vs initial phase significantly in the sky wherein the accuracy of the amplitude parameters of a GW has been deteriorated. The proposed method suppresses the systematic error of a GW depending on the sky region and allows us investigating the cosmological information more precisely.