Abstract Details

Name: Shyam Sunder
Affiliation: National Centre for Radio Astrophysics - Tata Institute of Fundamental Research
Conference ID: ASI2021_98
Title : Wide-band Timing of Millisecond Pulsars with GMRT
Authors and Co-Authors : Shyam Sunder (NCRA-TIFR), Jayanta Roy (NCRA-TIFR), Bhaswati Bhattacharyya (NCRA-TIFR), Lina Levin (University of Manchester), Ben Stappers (University of Manchester)
Abstract Type : Oral
Abstract Category : Stars, ISM and Galaxy
Abstract : Extreme rotational stability of the millisecond pulsars allow these to be used for pulsar timing array experiments aiming to prove nanoHertz Gravitational waves. Goal of this project is the estimation of precise time of arrivals (TOAs) for wide-band observations, which is of utmost importance for the pulsar timing experiments. The advent of new wide-band receivers with larger fractional bandwidth, like the upgraded GMRT, introduces new challenges due to non-negligible frequency dependent effects. In order to be benefited by the larger instantaneous observing bandwidth of the radio telescopes, the pulsar timing experiments requires modelling of pulse profile as function of radio frequency while estimating TOAs (Pennucci et al. 2016; Pennucci & Demorest 2018). Pennucci et al. 2014 presented an algorithm which enables us to simultaneously measure TOA and line of sight dispersion measure (DM) from the wide-band observations. We have implemented this method of wide-band timing for the frequency range 300-500MHz of upgraded GMRT to improve TOA precision while accounting for profile evolution with frequency and epoch to epoch DM variations. I'll present recent results from timing studies of a bunch of MSPs highlighting the advantage of the newly implemented wide-band timing method over the conventional narrow-band approach.