Abstract
The Askaryan Radio Array (ARA) is an ultrahigh energy (UHE, ) neutrino detector designed to observe neutrinos by searching for the radio waves emitted by the relativistic products of neutrino-nucleon interactions in Antarctic ice. In this paper, we present constraints on the diffuse flux of ultrahigh energy neutrinos between and resulting from a search for neutrinos in two complementary analyses, both analyzing four years of data (2013–2016) from the two deep stations (A2, A3) operating at that time. We place a 90% CL upper limit on the diffuse all flavor neutrino flux at of . This analysis includes four times the exposure of the previous ARA result and represents approximately th the exposure expected from operating ARA until the end of 2022.
4 More- Received 11 May 2020
- Accepted 15 July 2020
DOI:https://doi.org/10.1103/PhysRevD.102.043021
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