Doubles the number of fast radio burst repeat sources

(Nanowerk News) An international team of astronomers has discovered 25 new sources of repeating fast radio bursts (FRBs), explosions in the sky that come from far beyond the Milky Way. This discovery brings the total number of confirmed FRB sources to 50. Based on data collected by the CHIME/FRB collaboration, a new study published in Astrophysics Journal (“CHIME/FRB Discovery of 25 Repetitive Fast Radio Burst Sources”), may also bring scientists closer to understanding the origins of this mysterious phenomenon.

A new way to identify FRBs

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

“We combed the data to find every repeat source detected so far, including the less obvious ones,” said Ziggy Pleunis, first author of the paper who started work 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 are critical to this study because we can now accurately calculate the probability that two or more bursts originating from the same location are not simply coincidence. This will be very useful for similar research in the future.”

“This new discovery will enable the scientific community to study more repeating FRBs in fantastic detail across the electromagnetic spectrum and help answer a major open question in the field: Do repeat and non-repeating FRBs originate in different populations?” Added Aaron Pearlman, an 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 research.”

“It is very interesting that CHIME/FRB saw multiple flashes of light from the same location, as this allows for a detailed investigation of their nature,” said Adaeze Ibik, a PhD student in the David A. Dunlap Department of Astronomy and Astrophysics at the University of Toronto, who has led galaxy search in which several newly identified repeating FRBs are embedded.

“We were able to study some of these recurring sources and have identified possible related galaxies for two of them.”

Explains the mysterious origins of FRBs

FRBs are considered one of the greatest mysteries in astronomy, but their exact origin is unknown. Astronomers know that they originate far beyond our Milky Way and were most likely produced by the ash left behind after stars die.

One unexpected finding described in this paper is that contrary to what was previously thought, all FRBs may be repeats, not just one off. Simply put, many repeating FRBs are surprisingly inactive, producing less than one burst per week, and that apparently one-off FRBs were not observed long enough until now to detect a second burst.

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

“FRBs were most likely generated by the remnants of a dying star’s explosion. By studying the sources of repeating FRBs in detail, we can study the environment in which these outbursts occur and better understand the final stages of a star’s life. We can also learn more about the material ejected before and during the death of a star, which is then returned to the galaxy where the FRB lives.”