Alladi Ramakrishnan Hall

The Indian Pulsar Timing Array (InPTA): Joining the global hunt for nanohertz gravitational waves and related sciences

Pratik Tarafdar

IMSc

We present InPTA DR1, the first official Indo-Japanese data contribution to the International Pulsar Timing Array (IPTA) consortium aiming to inaugurate the era of nanohertz gravitational wave astronomy in the very near future. Our data enriches the pool being populated by PTAs around the globe such as NANOGrav, European Pulsar Timing Array and Parkes Pulsar Timing Array. It expands the overall frequency coverage and sensitivity of the combined dataset for incorporation in the upcoming third data release by the IPTA. This is expected to play a critical role in the first-ever detection of nanohertz gravitational waves. InPTA DR1 comprises the pulse arrival times, timing solutions and the highest-precision interstellar dispersion measures obtained so far, for fourteen millisecond pulsars chosen from the IPTA sample. The time baseline of the current release spans over 3.5 years of data obtained using the upgraded Giant Metrewave Radio Telescope (uGMRT). This dataset forms the basis of our recent studies and findings including recent profile change event in PSR J1713+0747, detection of CME with pulsar timing, investigation of scatter broadening in MSPs, wideband timing, single pulsar noise analysis, and chromaticity of decorrelation bandwidths and dispersion measures.