Doubling the number of sources of repeating fast radio bursts

Newswise —

McGill University astronomers are among a global group that located 25 more sources of repeating fast radio bursts (FRBs), these celestial blasts that originate from distant areas outside our Milky Way. This new discovery now increases the verified FRB sources to 50. Using information collected by the CHIME/FRB collaboration, the latest report released in The Astrophysical Journal today may move scientists one step closer to comprehending the sources of these enigmatic occurrences.

A new way of identifying FRBs

The proliferation of radio telescopes such as CHIME, which survey the entire northern hemisphere each day, has enabled an exponential rise in the count of FRBs detected over recent years. During the period spanning September 30, 2019, to May 1, 2021, the research team deployed a fresh collection of statistical methods that they had formulated to evaluate the CHIME data and confirm the authenticity of the FRBs they had identified.

Ziggy Pleunis, the lead author of the paper and a former PhD student at McGill University who now serves as a Dunlap Postdoctoral Fellow at the Dunlap Institute for Astronomy and Astrophysics, remarks, “We meticulously analyzed the data to identify all repeating sources discovered to date, even those that were less conspicuous." He further adds, "Our team devised novel statistical tools crucial to this study, which enabled us to precisely determine the likelihood of multiple bursts originating from comparable positions being more than a chance occurrence. These tools will prove highly beneficial for future research in this area.”

Aaron Pearlman, an FRQNT postdoctoral fellow at McGill University’s Trottier Space Institute and a collaborator on the paper, affirms that "These new discoveries will provide the scientific community with an opportunity to study an even greater number of repeating FRBs, delving deeper into the full electromagnetic spectrum and potentially resolving a fundamental question in the field: Do repeating and non-repeating FRBs come from separate populations?" He goes on to say, "I am thrilled about the forthcoming insights that our research will unlock."

Adaeze Ibik, a PhD student in the David A. Dunlap Department for Astronomy and Astrophysics at the University of Toronto, who spearheaded the hunt for the galaxies in which several of the newly discovered repeating FRBs are situated, remarks, "It is fascinating that CHIME/FRB detected multiple flashes from the same regions since this facilitates an in-depth investigation into their intrinsic nature."

Shedding light on the mysterious origins of FRBs

FRBs remain one of the most significant enigmas in astronomy, and their precise origins remain elusive. Nonetheless, scientists have determined that these explosions in the sky emanate from remote regions beyond our Milky Way galaxy and are probably generated by the remnants of stars that have perished.

The paper describes an unanticipated outcome, indicating that all FRBs might be repeaters, contradicting the earlier notion that some were one-time events. The reason for this is that many of the repeating FRBs have low activity levels, resulting in less than one burst per week, while the seemingly non-repeating FRBs have not been observed long enough until now for a subsequent burst to be identified.

Pleunis notes that this new research brings us closer to understanding what FRBs are.

“FRBs are most likely generated by the remnants of stars that have undergone explosive deaths. Through a thorough investigation of repeating FRB sources, we can examine the surroundings where these explosions occur and gain a better understanding of a star's ultimate stages. Additionally, we can learn more about the material that is ejected before and during the star's collapse, which is subsequently reintegrated into the galaxies in which the FRBs are situated," explains the researcher.

The study:

“CHIME/FRB Discovery of 25 Repeating Fast Radio Burst Sources” by Bridget Andersen et al published in The Astrophysical Journal
DOI: 10.3847/1538-4357/acc6c1

The Trottier Institute:

The Trottier Space Institute at McGill is an interdisciplinary center that brings together researchers engaged in astrophysics, planetary science, atmospheric science, astrobiology and other space-related research at McGill University. The main goals of the Institute are to:

• Provide an intellectual home for faculty, research staff, and students engaged in astrophysics, planetary science, and other space-related research at McGill University.
• Support the development of technology and instrumentation for space-related research.
• Foster cross-fertilization and interdisciplinary interactions and collaborations among Institute members in Institute-relevant research areas.
• Share with students, educators, and the public an understanding of and an appreciation for the goals, techniques and results of the Institute's research.