Updating the first CHIME/FRB catalog of fast radio bursts with baseband data

The CHIME/FRB Collaboration, :, Mandana Amiri, Bridget C. Andersen, Shion Andrew, Kevin Bandura, Mohit Bhardwaj, P. J. Boyle, Charanjot Brar, Daniela Breitman, Tomas Cassanelli, Pragya Chawla, Amanda M. Cook, Alice P. Curtin, Matt Dobbs, Fengqiu Adam Dong, Gwendolyn Eadie, Emmanuel Fonseca, B. M. Gaensler, Utkarsh Giri, Antonio Herrera-Martin, Hans Hopkins, Adaeze L. Ibik, Ronniy C. Joseph, J. F. Kaczmarek, Zarif Kader, Victoria M. Kaspi, Adam E. Lanman, Mattias Lazda, Calvin Leung, Siqi Liu, Juan Mena-Parra, Marcus Merryfield, Daniele Michilli, Cherry Ng, Kenzie Nimmo, Gavin Noble, Ayush Pandhi, Chitrang Patel, Aaron B. Pearlman, Ue-Li Pen, Emily Petroff, Ziggy Pleunis, Masoud Rafiei-Ravandi, Mubdi Rahman, Scott M. Ransom, Ketan R. Sand, Paul Scholz, Vishwangi Shah, Kaitlyn Shin, Yuliya Shpunarska, Seth R. Siegel, Kendrick Smith, Ingrid Stairs, David C. Stenning, Keith Vanderlinde, Haochen Wang, Henry White, Dallas Wulf

Published 2023-10-31Version 1

In 2021, a catalog of 536 fast radio bursts (FRBs) detected with the Canadian Hydrogen Intensity Mapping Experiment (CHIME) radio telescope was released by the CHIME/FRB Collaboration. This large collection of bursts, observed with a single instrument and uniform selection effects, has advanced our understanding of the FRB population. Here we update the results for 140 of these FRBs for which channelized raw voltage (baseband) data are available. With the voltages measured by the telescope's antennas, it is possible to maximize the telescope sensitivity in any direction within the primary beam, an operation called beamforming. This allows us to increase the signal-to-noise ratio (S/N) of the bursts and to localize them to sub-arcminute precision. The improved localization is also used to correct the beam response of the instrument and to measure fluxes and fluences with a ~ 10% uncertainty. Additionally, the time resolution is increased by three orders of magnitude relative to that in the first CHIME/FRB catalog, and, applying coherent dedispersion, burst morphologies can be studied in detail. Polarization information is also available for the full sample of 140 FRBs, providing an unprecedented dataset to study the polarization properties of the population. We release the baseband data beamformed to the most probable position of each FRB. These data are analyzed in detail in a series of accompanying papers.