It is he that sitteth upon the circle of the earth,
and the inhabitants thereof are as grasshoppers;
that stretcheth out the heavens as a curtain,
and spreadeth them out as a tent to dwell in:
Isaiah 40:22
"An astonishing eight new repeating radio signals known as fast radio bursts (FRBs) have been detected flaring from deep space.
At the start of 2019, just one of these mysterious signals, FRB 121102, was known to flash repeatedly. In January, scientists reported a second repeating one (FRB 180814).
This new paper - available on preprint server arXiv, and submitted to The Astrophysical Journal Letters - describes eight new repeating signals detected by the Canadian Hydrogen Intensity Mapping Experiment (CHIME) radio telescope.
Fast radio bursts are certainly perplexing. They are detected as spikes in radio data, lasting just a few milliseconds. But, in that time, they can discharge more energy than 500 million Suns.
Most FRBs are only detected once and can't be predicted, so tracing them back to their source is really tricky.
The individual bursts from repeaters seem to last a little bit longer than the bursts from one-off FRBs. That's pretty interesting.
There's also the frequency drift. The first two repeaters - FRB 121102 and FRB 180814 - showed a downward drift in frequency, with each burst getting successively lower.
Most of the eight new repeaters,also demonstrated this downward frequency drift. This could be a clue as to what's producing the signals.
The polarisation of the signals (how twisted the signal is) is informative, too. If the signal is really twisted up, it means it came from an extreme magnetic environment, such as can be found around a black hole or neutron star. This is what the signal from FRB 121102 was like.
But the team was able to measure the polarisation of one of the new signals, FRB 180916, and it was really low. This tells us that not all repeating FRBs come from extreme environments."
ScienceAlert
and the inhabitants thereof are as grasshoppers;
that stretcheth out the heavens as a curtain,
and spreadeth them out as a tent to dwell in:
Isaiah 40:22
"An astonishing eight new repeating radio signals known as fast radio bursts (FRBs) have been detected flaring from deep space.
At the start of 2019, just one of these mysterious signals, FRB 121102, was known to flash repeatedly. In January, scientists reported a second repeating one (FRB 180814).
This new paper - available on preprint server arXiv, and submitted to The Astrophysical Journal Letters - describes eight new repeating signals detected by the Canadian Hydrogen Intensity Mapping Experiment (CHIME) radio telescope.
Fast radio bursts are certainly perplexing. They are detected as spikes in radio data, lasting just a few milliseconds. But, in that time, they can discharge more energy than 500 million Suns.
Most FRBs are only detected once and can't be predicted, so tracing them back to their source is really tricky.
The individual bursts from repeaters seem to last a little bit longer than the bursts from one-off FRBs. That's pretty interesting.
There's also the frequency drift. The first two repeaters - FRB 121102 and FRB 180814 - showed a downward drift in frequency, with each burst getting successively lower.
Most of the eight new repeaters,also demonstrated this downward frequency drift. This could be a clue as to what's producing the signals.
The polarisation of the signals (how twisted the signal is) is informative, too. If the signal is really twisted up, it means it came from an extreme magnetic environment, such as can be found around a black hole or neutron star. This is what the signal from FRB 121102 was like.
But the team was able to measure the polarisation of one of the new signals, FRB 180916, and it was really low. This tells us that not all repeating FRBs come from extreme environments."
ScienceAlert
