The Astrophysical Journal (Jan 2025)
Morphology of 137 Fast Radio Bursts Down to Microsecond Timescales from the First CHIME/FRB Baseband Catalog
- Ketan R. Sand,
- Alice P. Curtin,
- Daniele Michilli,
- Victoria M. Kaspi,
- Emmanuel Fonseca,
- Kenzie Nimmo,
- Ziggy Pleunis,
- Kaitlyn Shin,
- Mohit Bhardwaj,
- Charanjot Brar,
- Matt Dobbs,
- Gwendolyn M. Eadie,
- B.M. Gaensler,
- Ronniy C. Joseph,
- Calvin Leung,
- Robert Main,
- Kiyoshi W. Masui,
- Ryan Mckinven,
- Ayush Pandhi,
- Aaron B. Pearlman,
- Masoud Rafiei-Ravandi,
- Mawson W. Sammons,
- Kendrick Smith,
- Ingrid H. Stairs
Affiliations
- Ketan R. Sand
- ORCiD
- Department of Physics, McGill University , 3600 rue University, Montréal, QC H3A 2T8, Canada ; [email protected]; Trottier Space Institute, McGill University , 3550 rue University, Montréal, QC H3A 2A7, Canada
- Alice P. Curtin
- ORCiD
- Department of Physics, McGill University , 3600 rue University, Montréal, QC H3A 2T8, Canada ; [email protected]; Trottier Space Institute, McGill University , 3550 rue University, Montréal, QC H3A 2A7, Canada
- Daniele Michilli
- ORCiD
- MIT Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology , 77 Massachusetts Avenue, Cambridge, MA 02139, USA; Department of Physics, Massachusetts Institute of Technology , 77 Massachusetts Avenue, Cambridge, MA 02139, USA
- Victoria M. Kaspi
- ORCiD
- Department of Physics, McGill University , 3600 rue University, Montréal, QC H3A 2T8, Canada ; [email protected]; Trottier Space Institute, McGill University , 3550 rue University, Montréal, QC H3A 2A7, Canada
- Emmanuel Fonseca
- ORCiD
- Department of Physics and Astronomy, West Virginia University , PO Box 6315, Morgantown, WV 26506, USA; Center for Gravitational Waves and Cosmology, West Virginia University , Chestnut Ridge Research Building, Morgantown, WV 26505, USA
- Kenzie Nimmo
- ORCiD
- MIT Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology , 77 Massachusetts Avenue, Cambridge, MA 02139, USA; Department of Physics, Massachusetts Institute of Technology , 77 Massachusetts Avenue, Cambridge, MA 02139, USA
- Ziggy Pleunis
- ORCiD
- Anton Pannekoek Institute for Astronomy, University of Amsterdam , Science Park 904, 1098 XH Amsterdam, The Netherlands; ASTRON , Netherlands Institute for Radio Astronomy, Oude Hoogeveensedijk 4, 7991 PD Dwingeloo, The Netherlands
- Kaitlyn Shin
- ORCiD
- MIT Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology , 77 Massachusetts Avenue, Cambridge, MA 02139, USA; Department of Physics, Massachusetts Institute of Technology , 77 Massachusetts Avenue, Cambridge, MA 02139, USA
- Mohit Bhardwaj
- ORCiD
- McWilliams Center for Cosmology, Department of Physics, Carnegie Mellon University , Pittsburgh, PA 15213, USA
- Charanjot Brar
- ORCiD
- Department of Physics, McGill University , 3600 rue University, Montréal, QC H3A 2T8, Canada ; [email protected]; Trottier Space Institute, McGill University , 3550 rue University, Montréal, QC H3A 2A7, Canada
- Matt Dobbs
- ORCiD
- Department of Physics, McGill University , 3600 rue University, Montréal, QC H3A 2T8, Canada ; [email protected]; Trottier Space Institute, McGill University , 3550 rue University, Montréal, QC H3A 2A7, Canada
- Gwendolyn M. Eadie
- ORCiD
- David A. Dunlap Department of Astronomy & Astrophysics, University of Toronto , 50 St. George Street, Toronto, ON M5S 3H4, Canada; Department of Statistical Sciences, University of Toronto , 700 University Avenue, 9th Floor, Toronto, ON M5G 1X6, Canada; Data Sciences Institute, University of Toronto , 700 University Avenue, 10th Floor, Toronto, ON M5G 1Z5, Canada
- B.M. Gaensler
- ORCiD
- David A. Dunlap Department of Astronomy & Astrophysics, University of Toronto , 50 St. George Street, Toronto, ON M5S 3H4, Canada; Department of Astronomy and Astrophysics, University of California Santa Cruz , 1156 High Street, Santa Cruz, CA 95064, USA; Dunlap Institute for Astronomy & Astrophysics, University of Toronto , 50 St. George Street, Toronto, ON M5S 3H4, Canada
- Ronniy C. Joseph
- ORCiD
- Department of Physics, McGill University , 3600 rue University, Montréal, QC H3A 2T8, Canada ; [email protected]; Trottier Space Institute, McGill University , 3550 rue University, Montréal, QC H3A 2A7, Canada
- Calvin Leung
- ORCiD
- Department of Astronomy, University of California Berkeley , Berkeley, CA 94720, USA
- Robert Main
- ORCiD
- Department of Physics, McGill University , 3600 rue University, Montréal, QC H3A 2T8, Canada ; [email protected]; Trottier Space Institute, McGill University , 3550 rue University, Montréal, QC H3A 2A7, Canada
- Kiyoshi W. Masui
- ORCiD
- MIT Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology , 77 Massachusetts Avenue, Cambridge, MA 02139, USA; Department of Physics, Massachusetts Institute of Technology , 77 Massachusetts Avenue, Cambridge, MA 02139, USA
- Ryan Mckinven
- ORCiD
- Department of Physics, McGill University , 3600 rue University, Montréal, QC H3A 2T8, Canada ; [email protected]; Trottier Space Institute, McGill University , 3550 rue University, Montréal, QC H3A 2A7, Canada
- Ayush Pandhi
- ORCiD
- David A. Dunlap Department of Astronomy & Astrophysics, University of Toronto , 50 St. George Street, Toronto, ON M5S 3H4, Canada; Dunlap Institute for Astronomy & Astrophysics, University of Toronto , 50 St. George Street, Toronto, ON M5S 3H4, Canada
- Aaron B. Pearlman
- ORCiD
- Department of Physics, McGill University , 3600 rue University, Montréal, QC H3A 2T8, Canada ; [email protected]; Trottier Space Institute, McGill University , 3550 rue University, Montréal, QC H3A 2A7, Canada
- Masoud Rafiei-Ravandi
- ORCiD
- Department of Physics, McGill University , 3600 rue University, Montréal, QC H3A 2T8, Canada ; [email protected]; Trottier Space Institute, McGill University , 3550 rue University, Montréal, QC H3A 2A7, Canada
- Mawson W. Sammons
- ORCiD
- Department of Physics, McGill University , 3600 rue University, Montréal, QC H3A 2T8, Canada ; [email protected]; Trottier Space Institute, McGill University , 3550 rue University, Montréal, QC H3A 2A7, Canada
- Kendrick Smith
- ORCiD
- Perimeter Institute for Theoretical Physics , 31 Caroline Street N, Waterloo, ON N25 2YL, Canada
- Ingrid H. Stairs
- ORCiD
- Department of Physics and Astronomy, University of British Columbia , 6224 Agricultural Road, Vancouver, BC V6T 1Z1, Canada
- DOI
- https://doi.org/10.3847/1538-4357/ad9b11
- Journal volume & issue
-
Vol. 979,
no. 2
p. 160
Abstract
We present a spectro-temporal analysis of 137 fast radio bursts (FRBs) from the first CHIME/FRB baseband catalog, including 125 one-off bursts and 12 repeat bursts, down to microsecond resolution using the least-squares optimization fitting routine fitburst . We measure subburst components within burst envelopes as narrow as ~23 μ s (FWHM), with 20% of the sample displaying substructures narrower than 100 μ s, offering constraints on emission mechanisms. Scattering timescales in the sample range from 30 μ s to 13 ms at 600 MHz. Our measured values are compared with those in the first CHIME/FRB intensity catalog, revealing that nearly one-third of our sample exhibits additional burst components at higher time resolutions. We observe no correlations between scattering time and dispersion measure, rotation measure, or linear polarization fraction, with the latter suggesting that depolarization due to multipath propagation is negligible in our sample. Bursts with narrower envelopes (≤1 ms) in our sample exhibit higher flux densities, indicating the potential presence of submillisecond FRBs that are being missed by our real-time system below a brightness threshold. Most multicomponent bursts in our sample exhibit subburst separations of ≤1 ms, with no bursts showing separations < 41 μ s, even at a time resolution of 2.56 μ s, but both scattering and low signal-to-noise ratio can hinder the detection of additional components. Lastly, given the morphological diversity of our sample, we suggest that one-off and repeating FRBs can come from different classes but have overlapping property distributions.
Keywords