The sensitivity of gravitational-waves detectors is characterized by their noise curves which determine the detector’s reach and the ability to accurately measure the parameters of astrophysical sources. The detector noise is typically modelled as stationary and Gaussian for many practical purposes. However, physical changes in the state of detectors due to environmental and instrumental factors, including extreme cases where a detector discontinues observing for some time, introduce non-stationarity into the noise. Even slow evolution of the detector sensitivity will affect long duration signals such as binary neutron star (BNS) mergers. Mis-estimation of the noise behavior directly impacts the posterior width of the signal parameters. This becomes an issue for studies which depend on accurate localization volumes such as i) probing cosmological parameters (such as Hubble constant, clustering bias) using cross-correlation methods with galaxies, ii) doing electromagnetic follow-up using localization information from parameter estimation done from pre-merger data. We study the effects of dynamical noise on the parameter estimation of the GW events. We develop a new method to correct dynamical noise by estimating a locally-valid pseudo-PSD which is normalized along the time-frequency track of a potential signal. In this talk, I will talk about modelling of GW detector noise, and how certain types of non-stationarities can be modelled for parameter estimation of GW signals. I will also talk about limitations and intended future improvements for the proposed method.
Zoom link: https://icts-res-in.zoom.us/j/85642222124?pwd=S3VhL0owOGV2VzRHWWFxaFQrRDFVQT09
Meeting ID: 856 4222 2124
Passcode: 272704