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.

Search for the anomalous events detected by ANITA using the Pierre Auger Observatory / Abdul Halim, A., Abreu, P., Aglietta, M., Allekotte, I., Almeida Cheminant, K., Almela, A., Aloisio, R., Alvarez-Muniz, J., Ammerman Yebra, J., Anastasi, G.A., Anchordoqui, L., Andrada, B., Andringa, S., Apollonio, L., Aramo, C., Araujo Ferreira, P.R., Arnone, E., Arteaga Velazquez, J.C., Assis, P., Avila, G., et al.. - In: PHYSICAL REVIEW LETTERS. - ISSN 0031-9007. - 134:12(2025), pp. 1-10. [10.1103/PhysRevLett.134.121003]

Search for the anomalous events detected by ANITA using the Pierre Auger Observatory

Mastrodicasa M.;
2025

Abstract

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.
2025
pierre auger observatory; upward-going showers; cosmic rays
01 Pubblicazione su rivista::01a Articolo in rivista
Search for the anomalous events detected by ANITA using the Pierre Auger Observatory / Abdul Halim, A., Abreu, P., Aglietta, M., Allekotte, I., Almeida Cheminant, K., Almela, A., Aloisio, R., Alvarez-Muniz, J., Ammerman Yebra, J., Anastasi, G.A., Anchordoqui, L., Andrada, B., Andringa, S., Apollonio, L., Aramo, C., Araujo Ferreira, P.R., Arnone, E., Arteaga Velazquez, J.C., Assis, P., Avila, G., et al.. - In: PHYSICAL REVIEW LETTERS. - ISSN 0031-9007. - 134:12(2025), pp. 1-10. [10.1103/PhysRevLett.134.121003]
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11573/1752726
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