Abstract Details

Name: Gaurav Waratkar
Affiliation: Indian Institute of Technology Bombay
Conference ID: ASI2021_396
Title : The Search for Fast Transients with AstroSat-CZTI
Authors and Co-Authors : Y. Sharma (Indian Institute of Technology Bombay & Division of Physics Mathematics and Astronomy California Institute of Technology), A. Marathe (Indian Institute of Technology Bombay and National Institute of Technology Karnataka), V. Bhalerao (Indian Institute of Technology Bombay), V. Shenoy (Indian Institute of Technology Bombay), G. Waratkar (Indian Institute of Technology Bombay), D. Nadella (National Institute of Technology Karnataka), P. Page (Indian Institute of Technology Bombay), P. Hebbar (Indian Institute of Technology Bombay and University of Alberta Edmonton), A. Vibhute (Inter-University Centre for Astronomy and Astrophysics India), D. Bhattacharya (Inter-University Centre for Astronomy and Astrophysics India), A.R. Rao (Tata Institute of Fundamental Research India), S. Vadawale (Physical Research Laboratory India)
Abstract Type : Oral
Abstract Category : Extragalactic Astronomy
Abstract : The Cadmium Zinc Telluride Imager on AstroSat has proven to be an effective all-sky monitor in the hard X-ray regime, detecting over 300 GRBs and putting highly competitive upper limits on X-ray emissions from gravitational wave (GW) sources and fast radio bursts (FRB) over the past 5 years. We introduce CIFT: the CZTI Interface for Fast Transients, a framework used to streamline searching for such transient sources in CZTI data, and for calculating upper limits in case of non-detections. We present, in detail, the algorithms used for searching for these transients in CZTI data and the methods used for placing upper limits on flux in case they are not detected. We also discuss the performance of our algorithms as compared to the other searches, including the details of 88 new transients detected in CZTI data. The addition of these 88 new GRBs to the already known count of 325 takes the GRB tally detected by CZTI to ~83 per year, comparable to ~92 per year detected on-board by Swift-BAT. Non-detections in the follow-up of some FRB and GW sources leading to stringent upper-limits are presented. Some future improvements to the interface, algorithms, and software that are currently ongoing are also discussed.