Far out cosmology: what are fast radio bursts (Introduction)

by David Turell @, Monday, November 16, 2020, 19:12 (1466 days ago) @ David Turell

We receive them, but what are they caused by?:

https://www.newscientist.com/article/2259924-repeated-radio-bursts-from-nearby-star-sug...

"Kirsten and his colleagues say they have detected two further weak bursts from SGR 1935+2154, each lasting just a millisecond and separated by 1.4 seconds. The weaker bursts were detected in May by the Westerbork Synthesis Radio Telescope in the Netherlands. Both of the May bursts were about 10,000 times weaker than April’s initial FRB.

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“'The exciting thing is these bursts bridge the gap between single pulses that are fairly weak and FRB-like bursts,” says Chris Bochenek at the California Institute of Technology, who led part of the initial discovery of the FRB source in April. “We [now] know there are processes happening all along this spectrum of energies.”

"An FRB is loosely defined as any radio burst that is bright enough to be seen from another galaxy. However, it is possible that these weaker bursts – only visible to astronomers because their source is relatively near to Earth – could be produced by the same mechanism as FRBs. They may even be FRBs, albeit weaker ones.

"At the moment, the mechanism of FRB production isn’t understood. “There are many theories,” says Daniele Michilli, a member of the CHIME team who is based at McGill University in Montreal, Canada. “The first class is where the emission comes from the magnetosphere of the star. A second class of theories is where there is like a fireball that ignites emission from a plasma cloud farther away from the star.”

"With more observations of magnetars like SGR 1935+2154, it may be possible to see more evidence of different ranges of burst activity. Factors such as the age of the star might play a role, say Kirsten and his colleagues, with younger magnetars producing brighter FRBs. Other cosmic objects, such as binary stars, could also be producing FRBs alongside magnetars.

“'This paper opens up new questions,” says Bochenek. “Is this like FRB emission? Where does one [emission] stop and the other one start? And what is an FRB?'”

Comment: Here we go again. The complexity of the activities of the universe grow and we don't know much about this one. All I can assume is God needed to create this function


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