The origin of these bright millisecond light flashes is unknown, as bursts or FRBs are unpredictable and quickly disappear. Scientists first observed them in 2007. Over the next decade, they observed only about 140 eruptions in the universe.
“The thing about the FRB is that they’re really hard to catch,” said Kiyoshi Masui, an assistant professor of physics at the Massachusetts Institute of Technology and a member of the Kavli University Institute of Astrophysics and Space Research. “You have to point your radio telescope at the right place at the right time, and you can’t predict where and when that will be.”
Most radio telescopes only see a spot the size of the moon in the sky at a time, which means that most of the FRBs remain invisible, Masui said.
That all changed when the CHIME telescope, located at the Dominion Radio Astrophysics Observatory in British Columbia, Canada, began receiving radio signals in 201
The stationary radio telescope, called the Canadian Hydrogen Intensity Mapping Experiment, discovered 535 new fast radio waves between 2018 and 2019.
The catalog not only expands a certain number of fast radio waves, but also expands the available information about their locations and properties. While most of the fast radio bursts occur only once, 61 of them repeat fast radio bursts from 18 sources. Repetitive series appear differently – each flash lasts a little longer than a single series.
When an explosion occurs again, scientists have a much better chance of tracing it back to its point of origin. These places can also help scientists determine the causes of outbreaks.
Based on their observations, the researchers believe that single fast radio bursts may have sources other than repetitive ones.
“With all these sources, we can really start to get an idea of what FRBs look like in general, what astrophysics might be driving these events, and how they can be used to explore the universe ahead,” said Caitlin Sheen, a CHIME member. and a graduate student in the Department of Physics at the Massachusetts Institute of Technology, in a statement.
How CHEIM works
The CHIME telescope functions slightly differently from the others used for radio astronomy. The array of four giant radio antennas, comparable in size and shape to the half-tubes used for snowboarding, are completely stationary. As the Earth rotates, this array receives radio signals from half the sky.
Usually radios move to pick up light from different areas of the sky. Instead, CHIME uses an all-digital design and has a correlator, a digital signal processor for capturing incoming radio signals. It can transfer huge amounts of data – about 7 terabits per second or the equivalent of a small percentage of global internet traffic.
“Digital signal processing is what makes CHIME capable of reconstructing and ‘looking’ in thousands of directions at once,” Masui said. “This is what helps us detect the FRB a thousand times more often than a traditional telescope.”
535 bursts discovered by CHIME came from all parts of the sky – and from space. Based on the information they have gathered, the researchers estimate that these bright fast radio bursts are likely to occur about 800 times a day across the sky.
“It’s a beautiful thing in this area – FRBs are really hard to see, but they’re not uncommon,” Masui said. “If your eyes could see flashes on the radio the way you can see camera flashes, you would see them all the time if you just looked up.
While these bursts would be intriguing enough based on their mysterious nature, scientists also believe they can use the bursts to have a better understanding of the universe and even distribute the distribution of gas in it.
When these radio waves travel through space, they are likely to encounter gas or plasma. This can distort the waves, change their properties and even their trajectory. Determining this information about a radio explosion can help scientists estimate the distance traveled and how much gas it has encountered.
“It carries a record of the structure of the universe that it went through to reach us from the source,” Masui said. “Therefore, we believe that they will be the best tool for studying the universe.”
Many of these bright radio bursts discovered by CHIME traveled from distant galaxies and were probably created by incredibly powerful energy sources – but researchers are still trying to determine the exact nature of these sources.
With fast enough radio bursts, it may be possible to outline the large-scale structure of the universe.
“These large structures make up the threads of the space network,” said Alex Josephie, a doctoral student in physics at McGill University in Canada. “With the FRB catalog, we found this connection between the FRB and the scale structure. It’s really exciting and introduces a new era of cosmology (rapid radio explosion).”