Snabb radio Burst FRB 20220610A, the most powerful radio burst ever observed was detected on 10 June 2022. It had originated from a source that existed 8.5 billion years ago when the universum was just 5 billion years old which makes the source farthest known for an FRB. The source was thought to be either a single, irregular galax or a group of three distant galaxies. However, study of images captured by Hubble telescope on follow-up after its discovery reveals seven sources, one of which was identified as the host galax. Värden galax was also determined to be a star-forming galax. The study identified the system as a compact galax group whose members showed signs of interaction among themselves. Galaxies in compact groups are uncommon, hence the finding of FRB 20220610A originating in such an environment presents a novel origin of FRBs.
Snabba radioskurar (FRBs), även kallade Lorimer Bursts är extremt energiska blixtar av radiovågor. De är mycket kortvariga i några millisekunder. Sedan dess första upptäckt 2007 av Duncan Lorimer har omkring 1000 FRB upptäckts.
Den snabba radioskuren FRB 20220610A upptäcktes den 10 juni 2022. Fyra gånger mer energisk än närmare FRB:er, det var den mest kraftfulla snabba radioskuren (FRB) som någonsin observerats. Det hade sitt ursprung från sin källa som fanns för 8.5 miljarder år sedan när universum var bara 5 miljarder år gammal. FRB hade rest i 8.5 miljarder år för att nå Hubble. The source was the farthest known so far for any FRB and thought to be either a single, irregular galax or a group of three distant galaxies.
Men skarpa bilder tagna av Hubble telescope on follow-up after its discovery has revealed that the source of FRB 20220610A was not ‘one monolithic galax’. Usually, FRBs originate from isolated galaxies. Instead, this fast radio burst had originated from an interacting system of at least seven galaxies in proximity on the path of merging. This development broadens the list of possible sources of FRBs.
The origin and mechanism of formation FBR is not clearly understood. Nevertheless, it is agreed that highly compact bodies like neutron stjärna or svart hål är involverade i generering av kraftfulla radiosprängningar. Extrema fysikfenomen som kollision av svart hål eller neutron stjärna, starquakes when the crust of a neutron stjärna undergoes sudden adjustments, sudden snaping of tangled magnetic fields of most intensely magnetic type of neutron stars (a process akin to formation of solar flares but at much higher scale), periodic interaction of magnetospheres of a pair of kretsande neutron stjärnor are some of possible mechanisms of formation of Fast radio bursts (FRBs).
Vetenskapen om ursprung och mekanism för bildande av snabba radioskurar (FRB) är i stort sett ofullständig, men den senaste studien fyller en viss kunskapslucka.
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Referenser:
- NASAs Hubble Mission Team. Nyheter – Hubble hittar ett konstigt hem för Farthest Fast Radio Burst. Upplagd 09 januari 2024. Tillgänglig på https://science.nasa.gov/missions/hubble/hubble-finds-weird-home-of-farthest-fast-radio-burst/
- Gordon AC, et al, 2023. A Fast Radio Burst in a Compact Galaxy Group på z~1. Förtryck arXiv:2311.10815v1. Inlämnad den 17 november 2023. DOI: https://doi.org/10.48550/arXiv.2311.10815
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