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Observation of Reconstructable Radio Emission Coincident with an X-Class Solar Flare in the Askaryan Radio Array Prototype Station

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 نشر من قبل Brian Clark
 تاريخ النشر 2018
  مجال البحث فيزياء
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The Askaryan Radio Array (ARA) reports an observation of radio emission coincident with the Valentines Day solar flare on Feb. 15$^{rm{th}}$, 2011 in the prototype Testbed station. We find $sim2000$ events that passed our neutrino search criteria during the 70 minute period of the flare, all of which reconstruct to the location of the sun. A signal analysis of the events reveals them to be consistent with that of bright thermal noise correlated across antennas. This is the first natural source of radio emission reported by ARA that is tightly reconstructable on an event-by-event basis. The observation is also the first for ARA to point radio from individual events to an extraterrestrial source on the sky. We comment on how the solar flares, coupled with improved systematic uncertainties in reconstruction algorithms, could aid in a mapping of any above-ice radio emission, such as that from cosmic-ray air showers, to astronomical locations on the sky.



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