[NTD, Beijing, July 23, 2022]Astronomers at the Massachusetts Institute of Technology (MIT) and universities in Canada and the United States say they have detected a radio signal from a distant galaxy that flashes repeatedly with surprising regularity, like a heartbeat.
The signal has been classified asfast radio burst（FRB), an intense burst of radio waves of unknown astrophysical origin, usually lasting a few milliseconds at most.
by the Canadian Hydrogen Intensity Mapping Experiment (CHIME) /FRBThe research, written by members of the collaboration, was published July 13 in the journal Nature.In the report, the scientists stated that afast radio burst(FRB) was found billions of light-years from Earth.
CHIME is an interferometric radio telescope at the Dominion Radio Astrophysical Observatory in British Columbia, Canada, designed to detect radio waves emitted by hydrogen in the early universe. Hundreds of fast radio bursts have been detected so far.
FRBs are radio waves with millisecond blink times, visible at distances of billions of light-years. The first FRB was discovered 15 years ago; while most observed FRBs are one-offs, astronomers have detected hundreds of FRBs to date.
The radio signal in this study was picked up in December 2019, and astronomers tagged it asFRB 20191221Aits exact origin remains a mystery.
Astronomers speculate that the signal may come from a magnetar or radio pulsar, a type of neutron star. Neutron stars are compact, spinning giant star collapsed cores.
However, most notablyFRB 20191221Aduration. This new signal is quite unique, it lasts as long as 3 seconds, which is about 1000 times longer than the average FRB. Within this window, the team detected bursts of radio waves that repeated every 0.2 seconds, with a distinct periodicity similar to a beating heart.
This signal is the longest-lasting FRB detected so far and has the clearest periodic pattern. The team detected bursts of radio waves that repeated in a clear pattern every 0.2 seconds.
“It’s very unusual,” Daniele Michilli, a postdoctoral fellow at MIT’s Kavli Institute for Astrophysics and Space, said in a statement. “Not only was it very long, lasting about three seconds, but There are also very precise periodic peaks, with a ‘bang, bang, bang’ every fraction of a second, like a heartbeat. (observed) The signal is periodic, for the first time .”
“The duration (about 3 seconds) and the pulse profile of 9 or more components make this signal an anomaly in the FRB group. Such a short periodicity provides strong evidence for the origin of neutron stars. Furthermore, our The detections favor emission from the neutron star’s magnetosphere, rather than the emission regions farther away from the star predicted by some models,” the team wrote.
Additionally, FRB 20191221A appears to be more than a million times brighter than the radio emissions of galactic pulsars and magnetars.
Midgley said the luminous flashes may have come from a distant radio pulsar or magnetar, which normally rotates less brightly, but for some unknown reason was lucky enough to capture a rare three-second window at CHIME , fired a series of bright bursts.
“CHIME has now detected many FRBs with different properties,” Midgley said. “We’ve seen some (FRBs) generated in very turbulent clouds, while others appear to be in clean environments. In. From the properties of this new signal, we can say that around this source, there is a cloud of plasma that must be very turbulent.”
The team’s goal is to detect more signals from this source, which MIT said in a press release could be used as an “astrophysical clock” — possibly even measuring how fast the universe is expanding.
Midgley said the detection raises the question of what causes this extreme signal we’ve never seen before and how we can use it to study the universe. Future telescopes are expected to spot thousands of FRBs each month, which could lead to the detection of “more of these periodic signals.”
(Transfer from The Epoch Times/Editor-in-charge: Ye Ping)
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