We present a search for the baryon number and lepton number violating decays and produced from the process, using a data sample collected by the Belle II experiment at the SuperKEKB collider. No evidence of signal is found in either decay mode, which have equal to 2 and 0, respectively. Upper limits at 90% credibility level on the branching fractions of and are determined to be and , respectively. Published by the American Physical Society2024
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This content will become publicly available on March 27, 2026
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 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 events from misreconstructed cosmic-ray showers. This translates to an upper bound on the integral flux of and for an and spectrum, respectively. An upward-going flux of showers normalized to the ANITA observations is shown to predict over 34 events for an spectrum and over 8.1 events for a conservative spectrum, in strong disagreement with the interpretation of the anomalous events as upward-going showers. Published by the American Physical Society2025
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- PAR ID:
- 10600566
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- 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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