Giant GRB Ring
The Giant GRB Ring is a ring of nine gamma-ray bursts (GRBs) that is the 2nd largest known cosmic structure in the observable universe. It was discovered in July 2015 by a team of Hungarian and American astronomers led by L.G. Balazs while exploring data from different gamma-ray and X-ray telescopes, in particular the Swift Spacecraft.
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Image Credit : Pablo Carlos Budassi
The ring of GRBs lies at a distance of approximately 9.1 billion light years from Earth at the redshift between 0.78 and 0.86 and measures about 1.72 gigaparsecs (5.6 billion light years) in diameter, making it one of the largest cosmic structures in our known universe.
Typically, the distribution of gamma ray bursts in the universe appears in the sets of less than the 2σ distribution, or with fewer than two GRBs in the mean data of the point-radius system. Thus, such a centralization as this appears extremely unlikely, given adopted theoretical models. Proposals include the presensce of a giant supergalactic structure. This would be an extremely huge cosmic structure of the universe, with a mean size of about 5.6 billion light years. Such a supercluster can interpret the significant distribution of GRBs because of its tie to star formation. If such a structure did exist, it would be one of the largest cosmic structures of the observable universe.
The Histoty of Discovery of Giant GRB Ring
In early July 2015, after the discovery of the Hercules-Corona Borealis Great Wall, I. Horvath, J. Hakkila and Z. Bagoly, among others, directed a further detailed analysis of the spatial distribution of gamma ray bursts within the distant universe. Provided by more than 15 years of data from the Swift Gamma-Ray Burst Mission, amongst other ground-based telescopes, they assessed the data to see if any more structures can be seen using the system of GRB correlation. Suddenly, they noticed a significant clustering of GRBs within z = 0.78 - 0.86, with nine GRBs condensed in that region of 43 by 30 degrees of the sky. With further tests and analyses of the clustering, they found out that the sample was indeed having a higher concentration than the expected normal level, indication of a massive galactic structure in the vicinity.
Characteristics of Giant GRB Ring
The paper released by the team did not show any data concerning the location of the largest cosmic structure. However, the distance and the size was given in the paper. It is approximately 9.1 billion light years from Earth and about 5.6 billion light years across.
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