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A fast radio burst (FRB) is a high energy astrophysical phenomenon manifested as a transient radio pulse lasting only a few milliseconds. FRBs show a frequency-dependent dispersion consistent with propagation through an ionized plasma.〔 eleven bursts have been detected, all but one by the Parkes radio telescope. The origin of FRBs is not known: they are generally thought to be extragalactic due to the anomalously high amount of pulse dispersion observed. It has also been suggested that they may originate from nearby stars.〔("Fast Radio Bursts Might Come From Nearby Stars", Harvard-Smithsonian centre for Astrophysics, December 12, 2013 )〕 It has also been speculated that they might be signs of extraterrestrial intelligence. FRBs are identified by the date the signal was recorded, as "YYMMDD" - e.g. one on 26 June 2011 would be called FRB 110626.〔 The oldest so far found is FRB 010621. On January 19, 2015, astronomers at Australia's national science agency (CSIRO) reported that, for the first time, a fast radio burst had been observed live (at Parkes).〔(【引用サイトリンク】 url=https://www.ras.org.uk/news-and-press/2578-cosmic-radio-burst-caught-red-handed )〕 Closely related to FRBs are Perytons, dispersed pulses which share some of the same characteristics as FRBs, but are of terrestrial origin. Perytons were shown in April 2015 to be due to emissions from premature opening of microwave oven doors in the Parkes observatory cafeteria,〔("Identifying the source of Perytons at the Parkes radio telescope" 2015 )〕 while FRBs remain as most likely high energy astrophysical sources. == Lorimer Burst == The burst was discovered in archived data taken in 2001 by the Parkes radio dish in Australia. Analysis of the survey data found a 30-jansky dispersed burst that occurred in 24 Aug 2001, less than 5 milliseconds in duration, located 3° from the Small Magellanic Cloud. The reported burst properties argue against a physical association with the Milky Way galaxy or the Small Magellanic Cloud. The burst became known as the Lorimer burst. The discoverers argue that current models for the free electron content in the universe imply that the burst is less than 1 gigaparsec distant. The fact that no further bursts were seen in 90 hours of additional observations implies that it was a singular event such as a supernova or merger of relativistic objects.〔 It is suggested that hundreds of similar events could occur every day and, if detected, could serve as cosmological probes. Radio pulsar surveys such as Astropulse and SETI@home offer one of the few opportunities to monitor the radio sky for impulsive burst-like events with millisecond durations. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Fast radio burst」の詳細全文を読む スポンサード リンク
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