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A Southern sky search for repeating Fast Radio Bursts using the Australian SKA Pathfinder

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 نشر من قبل Shivani Bhandari Miss
 تاريخ النشر 2019
  مجال البحث فيزياء
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We have conducted a search for bright repeating Fast Radio Bursts in our nearby Universe with the Australian Square Kilometer Array Pathfinder (ASKAP) in single-dish mode. We used eight ASKAP 12-m dishes, each equipped with a Chequerboard Phased Array Feed forming 36 beams on the sky, to survey $sim$30,000 deg$^{2}$ of the southern sky ($-90^{circ} < delta < +30^{circ}$) in 158 antenna days. The fluence limit of the survey is 22 Jyms. We report the detection of FRB 180515 in our survey. We found no repeating FRBs in a total mean observation of 3hrs per pointing divided into one-hour intervals, which were separated in time ranging between a day to a month. Using our non-detection, we exclude the presence of a repeating FRB similar to FRB 121102 closer than $z=0.004$ in the survey area --- a volume of at least $9.4 times 10^4$Mpc$^3$ --- at 95% confidence.



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