New technique to identify FRBs offers promise of new discoveries

A new way to identify FRBs

Thanks to radio telescopes like CHIME’s, which scan the entire northern sky every day, the number of FRBs detected has grown exponentially in recent years. The research team used a new set of statistical tools they developed to review data collected by CHIME between September 30, 2019, and May 1, 2021, to confirm whether what they said was indeed FRB.

“We combed through the data to find all the repetitive sources detected so far, including the less obvious ones,” says Ziggy Pleunis, the paper’s first author who began working on the research as a PhD student at McGill University. He is now a Dunlap Postdoctoral Fellow at the Dunlap Institute for Astronomy and Astrophysics. “These new tools were essential to this study because we can now accurately calculate the probability that two or more explosions coming from similar locations are not just a coincidence. It should be very useful for similar research in the future.”

“These new discoveries will allow the scientific community to study more repeating FRBs in fantastic detail across the electromagnetic spectrum and will help answer an important open question in the field: Do repeating and non-repeating FRBs originate from different populations? Adds Aaron Pearlman, a FRQNT postdoctoral fellow at McGill University’s Trottier Space Institute, who also collaborated on the paper. “I am excited about the new insights that will be unlocked as a result of our study.”

“It is exciting that CHIME/FRB has seen several flashes from the same locations, as this allows for detailed investigation of their nature,” says Adaeze Ibik, a doctoral student in the David A. Dunlap Department of Astronomy and Astrophysics at the University of Toronto, which has led the search for the galaxies in which some of the recently identified FRB repeats are embedded.

“We were able to zero in on some of these repetitive sources and have already identified probable partner galaxies for two of them.”

Shedding light on the mysterious origins of FRBs

FRBs are considered one of the biggest mysteries in astronomy, but their exact origins are unknown. Astronomers know that they come from far away from our Milky Way and are most likely produced by ash left over after stars die.

An unexpected finding described in the paper is that, contrary to what was previously thought, all FRBs may be repeaters rather than unique. It’s simply that many repetitive FRBs are surprisingly inactive, producing less than one burst per week, and that apparently unique FRBs simply haven’t been observed long enough so far to detect a second burst.

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

“FRBs are likely produced by the remnants of explosive stellar deaths. By studying repeating FRB sources in detail, we can study the environments in which these explosions occur and better understand the final stages of a star’s life. We can also learn more about the material that is ejected before and during the disappearance of the star, which is then returned to the galaxies in which the FRBs live.”