Researchers detect the most powerful gamma-ray flare in history
On October 9, telescopes around the world spotted an enormous flare of radiation the likes of which had never been seen before, dubbed Swift J1913.1+ 1946.
Scientists initially thought it was a short flash of X-rays from a source not too far away. With further studies, they discovered the reality of the glow: a gamma-ray burst; One of the most powerful explosions in the universe and has now been renamed as GRB221009A.
This glow is the closest to us, 2.4 billion light-years away, and is the most energetic of all. It reaches 18 TeV, and although it's 20 times closer to the average long gamma ray burst, it doesn't pose a threat to the planet. As a result of GRB221009A's proximity to us it looked very bright and is probably the brightest gamma ray burst we've ever seen.
“This is a very exciting event,” said astronomer Gemma Anderson of Curtin University, affiliated with the International Center for Radio Astronomy Research (ICRAR) in Australia. “Scientists were able to observe this explosion; Because it is very close and powerful. The radio, light, x-rays and gamma rays resulting from it are very bright and light up and fade away. Therefore, many telescopes around the world can study this explosion and collect complete data about it.
Gamma radiation is produced by the radioactive decay of atomic nuclei and is the most powerful form of light in the universe. It empties an amount of energy equal to the energy produced by the sun in 10 billion years in a few seconds. It represents the end of a huge star - a supernova - and may also result from the collision of two neutron stars, which results in A massive explosion (supernova) when the external pressure of a star (about eight times the mass of our Sun) decreases and then collapses under the influence of gravity; The outer matter shoots out into space while the core collapses into a neutron star or black hole.
Astronomers observed a collision between two neutron stars in 2017 that resulted in a brief gamma-ray burst. Long-duration bursts are usually associated with powerful superluminous supernova events. However, it is not clear what we are looking for with GRB221009A.
“It's still too early to tell, as it takes days for light from a supernova to reach us and for us to notice it,” Anderson says. however; This gamma-ray burst has a long duration and could be a very powerful type of supernova.”
This explosion appears to have come from a very dusty galaxy and is very powerful. The Chinese LHAASO Cosmic Ray Observatory and the Cherenkov Observatory in China have detected photons with energies of about 18 TeV.
So far, only a few gamma-ray bursts have been detected with emission in the TeV range, and if the LHAASO data are confirmed, the GRB221009A burst will be the first above 10 TeV.
Scientists set telescopes at the site of the explosion to observe the behavior of the next flare across as many wavelengths as possible, information that will reveal in detail the cause of the explosion.
"When we're dealing with cosmic explosions, stellar explosions stay close to the speed of light leaving a black hole in their wake," Anderson says. "We still don't fully understand this process." Such a close explosion enables us to collect accurate data to study and understand how such explosions occur.
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