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Title: Search for the Anomalous Events Detected by ANITA Using the Pierre Auger Observatory
A dedicated search for upward-going air showers at zenith angles exceeding 110° and energies E > 0.1 EeV has been performed using the Fluorescence Detector of the Pierre Auger Observatory. The search is motivated by two “anomalous” radio pulses observed by the ANITA flights I and III that appear inconsistent with the standard model of particle physics. Using simulations of both regular cosmic-ray showers and upward-going events, a selection procedure has been defined to separate potential upward-going candidate events and the corresponding exposure has been calculated in the energy range [0.1–33] EeV. One event has been found in the search period between January 1, 2004, and December 31, 2018, consistent with an expected background of 0.27 ± 0.12 events from misreconstructed cosmic-ray showers. This translates to an upper bound on the integral flux of ( 7.2 ± 0.2 ) × 10 21 cm 2 sr 1 y 1 and ( 3.6 ± 0.2 ) × 10 20 cm 2 sr 1 y 1 for an E 1 and E 2 spectrum, respectively. An upward-going flux of showers normalized to the ANITA observations is shown to predict over 34 events for an E 3 spectrum and over 8.1 events for a conservative E 5 spectrum, in strong disagreement with the interpretation of the anomalous events as upward-going showers. Published by the American Physical Society2025  more » « less
Award ID(s):
2412679 2310111
PAR ID:
10600566
Author(s) / Creator(s):
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Corporate Creator(s):
Publisher / Repository:
APS
Date Published:
Journal Name:
Physical Review Letters
Volume:
134
Issue:
12
ISSN:
0031-9007
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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