The Astrophysical Journal (Jan 2023)
An FRB Sent Me a DM: Constraining the Electron Column of the Milky Way Halo with Fast Radio Burst Dispersion Measures from CHIME/FRB
- Amanda M. Cook,
- Mohit Bhardwaj,
- B. M. Gaensler,
- Paul Scholz,
- Gwendolyn M. Eadie,
- Alex S. Hill,
- Victoria M. Kaspi,
- Kiyoshi W. Masui,
- Alice P. Curtin,
- Fengqiu Adam Dong,
- Emmanuel Fonseca,
- Antonio Herrera-Martin,
- Jane Kaczmarek,
- Adam E. Lanman,
- Mattias Lazda,
- Calvin Leung,
- Bradley W. Meyers,
- Daniele Michilli,
- Ayush Pandhi,
- Aaron B. Pearlman,
- Ziggy Pleunis,
- Scott Ransom,
- Mubdi Rahman,
- Ketan R. Sand,
- Kaitlyn Shin,
- Kendrick Smith,
- Ingrid Stairs,
- David C. Stenning
Affiliations
- Amanda M. Cook
- ORCiD
- David A. Dunlap Institute Department of Astronomy & Astrophysics, University of Toronto , 50 St. George Street, Toronto, ON M5S 3H4, Canada ; [email protected]; Dunlap Institute for Astronomy & Astrophysics, University of Toronto , 50 St. George Street, Toronto, ON M5S 3H4, Canada
- Mohit Bhardwaj
- ORCiD
- McGill Space Institute, McGill University , 3550 rue University, Montréal, QC H3A 2A7, Canada; Department of Physics, McGill University , 3600 rue University, Montréal, QC H3A 2T8, Canada; Department of Physics, Carnegie Mellon University , 5000 Forbes Avenue, Pittsburgh, PA 15213, USA
- B. M. Gaensler
- ORCiD
- David A. Dunlap Institute Department of Astronomy & Astrophysics, University of Toronto , 50 St. George Street, Toronto, ON M5S 3H4, Canada ; [email protected]; Dunlap Institute for Astronomy & Astrophysics, University of Toronto , 50 St. George Street, Toronto, ON M5S 3H4, Canada
- Paul Scholz
- ORCiD
- Dunlap Institute for Astronomy & Astrophysics, University of Toronto , 50 St. George Street, Toronto, ON M5S 3H4, Canada
- Gwendolyn M. Eadie
- ORCiD
- David A. Dunlap Institute Department of Astronomy & Astrophysics, University of Toronto , 50 St. George Street, Toronto, ON M5S 3H4, Canada ; [email protected]; Department of Statistical Science, University of Toronto , Ontario Power Building, 700 University Avenue, 9th Floor, Toronto, ON M5G 1Z5, Canada
- Alex S. Hill
- ORCiD
- Dominion Radio Astrophysical Observatory, Herzberg Research Centre for Astronomy and Astrophysics , National Research Council Canada, P.O. Box 248, Penticton, BC V2A 6J9, Canada; Department of Physics and Astronomy, University of British Columbia , 6224 Agricultural Road, Vancouver, BC V6T 1Z1 Canada
- Victoria M. Kaspi
- ORCiD
- McGill Space Institute, McGill University , 3550 rue University, Montréal, QC H3A 2A7, Canada; Department of Physics, McGill University , 3600 rue University, Montréal, QC H3A 2T8, 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
- Alice P. Curtin
- ORCiD
- McGill Space Institute, McGill University , 3550 rue University, Montréal, QC H3A 2A7, Canada; Department of Physics, McGill University , 3600 rue University, Montréal, QC H3A 2T8, Canada
- Fengqiu Adam Dong
- ORCiD
- Department of Physics and Astronomy, University of British Columbia , 6224 Agricultural Road, Vancouver, BC V6T 1Z1 Canada
- Emmanuel Fonseca
- ORCiD
- Department of Physics and Astronomy, West Virginia University , P.O. Box 6315, Morgantown, WV 26506, USA; Center for Gravitational Waves and Cosmology, West Virginia University , Chestnut Ridge Research Building, Morgantown, WV 26505, USA
- Antonio Herrera-Martin
- ORCiD
- David A. Dunlap Institute Department of Astronomy & Astrophysics, University of Toronto , 50 St. George Street, Toronto, ON M5S 3H4, Canada ; [email protected]; Department of Statistical Science, University of Toronto , Ontario Power Building, 700 University Avenue, 9th Floor, Toronto, ON M5G 1Z5, Canada
- Jane Kaczmarek
- ORCiD
- Dominion Radio Astrophysical Observatory, Herzberg Research Centre for Astronomy and Astrophysics , National Research Council Canada, P.O. Box 248, Penticton, BC V2A 6J9, Canada
- Adam E. Lanman
- ORCiD
- McGill Space Institute, McGill University , 3550 rue University, Montréal, QC H3A 2A7, Canada; Department of Physics, McGill University , 3600 rue University, Montréal, QC H3A 2T8, Canada
- Mattias Lazda
- ORCiD
- Department of Physics, McGill University , 3600 rue University, Montréal, QC H3A 2T8, Canada
- Calvin Leung
- 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
- Bradley W. Meyers
- ORCiD
- Department of Physics and Astronomy, University of British Columbia , 6224 Agricultural Road, Vancouver, BC V6T 1Z1 Canada; International Centre for Radio Astronomy Research (ICRAR), Curtin University , Bentley, WA 6102, Australia
- 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
- Ayush Pandhi
- ORCiD
- David A. Dunlap Institute Department of Astronomy & Astrophysics, University of Toronto , 50 St. George Street, Toronto, ON M5S 3H4, Canada ; [email protected]; Dunlap Institute for Astronomy & Astrophysics, University of Toronto , 50 St. George Street, Toronto, ON M5S 3H4, Canada
- Aaron B. Pearlman
- ORCiD
- McGill Space Institute, McGill University , 3550 rue University, Montréal, QC H3A 2A7, Canada; Department of Physics, McGill University , 3600 rue University, Montréal, QC H3A 2T8, Canada
- Ziggy Pleunis
- ORCiD
- Dunlap Institute for Astronomy & Astrophysics, University of Toronto , 50 St. George Street, Toronto, ON M5S 3H4, Canada
- Scott Ransom
- ORCiD
- National Radio Astronomy Observatory , 520 Edgemont Road, Charlottesville, VA 22903, USA
- Mubdi Rahman
- ORCiD
- Sidrat Research , P.O. Box 73527 RPO Wychwood, Toronto, ON M6C 4A7, Canada
- Ketan R. Sand
- ORCiD
- McGill Space Institute, McGill University , 3550 rue University, Montréal, QC H3A 2A7, Canada; Department of Physics, McGill University , 3600 rue University, Montréal, QC H3A 2T8, Canada
- 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
- Kendrick Smith
- ORCiD
- Perimeter Institute for Theoretical Physics , 31 Caroline Street N, Waterloo, ON N25 2YL, Canada
- Ingrid Stairs
- ORCiD
- Department of Physics and Astronomy, University of British Columbia , 6224 Agricultural Road, Vancouver, BC V6T 1Z1 Canada
- David C. Stenning
- ORCiD
- Department of Statistics & Actuarial Science, Simon Fraser University , Burnaby, BC, Canada
- DOI
- https://doi.org/10.3847/1538-4357/acbbd0
- Journal volume & issue
-
Vol. 946,
no. 2
p. 58
Abstract
The CHIME/FRB project has detected hundreds of fast radio bursts (FRBs), providing an unparalleled population to statistically probe the foreground media that they illuminate. One such foreground medium is the ionized halo of the Milky Way (MW). We estimate the total Galactic electron column density from FRB dispersion measures (DMs) as a function of Galactic latitude using four different estimators, including ones that assume spherical symmetry of the ionized MW halo and ones that imply more latitudinal variation in density. Our observation-based constraints of the total Galactic DM contribution for ∣ b ∣ ≥ 30°, depending on the Galactic latitude and selected model, span 87.8–141 pc cm ^−3 . This constraint implies upper limits on the MW halo DM contribution that range over 52–111 pc cm ^−3 . We discuss the viability of various gas density profiles for the MW halo that have been used to estimate the halo’s contribution to DMs of extragalactic sources. Several models overestimate the DM contribution, especially when assuming higher halo gas masses (∼3.5 × 10 ^12 M _⊙ ). Some halo models predict a higher MW halo DM contribution than can be supported by our observations unless the effect of feedback is increased within them, highlighting the impact of feedback processes in galaxy formation.
Keywords
- Galactic radio sources
- Radio bursts
- Circumgalactic medium
- Galaxy structure
- Hot ionized medium
- Warm ionized medium
