Search for Large-Scale Cosmic-Ray Anisotropy with the First Detection Units of KM3NeT/ARCA

KM3NeT Collaboration

doi:10.22323/1.501.0202

Search for Large-Scale Cosmic-Ray Anisotropy with the First Detection Units of KM3NeT/ARCA

KM3NeT Collaboration

Physics

Badji Mokhtar University
University of Florence
National Institute for Nuclear Physics
Université de Strasbourg
Université de Haute-Alsace
Khalifa University of Science and Technology
Aix-Marseille Université
University of Valencia
University of Rome La Sapienza
Polytechnic University of Catalonia
Nantes Université
Polytechnic University of Valencia
Université de Paris
University of Genoa
Université de Caen
North West University
University of Bologna
University of Campania Luigi Vanvitelli
University of Hull
Czech Technical University in Prague
Comenius University
National Institute for Subatomic Physics
Mohammed V University in Rabat
University of Salerno
University of Naples Federico II
National Institute for Laser, Plasma and Radiation Physics
University of Amsterdam
Netherlands Organisation for Applied Scientific Research
Cadi Ayyad University
University of the Witwatersrand
University of Catania
Princeton University
Université catholique de Louvain
University of Granada
Friedrich-Alexander University Erlangen-Nürnberg
Demokritos National Centre for Scientific Research
Mohamed I University
Western Sydney University
Royal Netherlands Institute for Sea Research - NIOZ
Leiden University
AGH University of Science and Technology
Nicolaus Copernicus Astronomical Center of the Polish Academy of Sciences
Ivane Javakhishvili Tbilisi State University
The University of Georgia, Tbilisi
Institut universitaire de France
Max Planck Institute for Radio Astronomy
Sharjah Academy for Astronomy, Space Sciences & Technology
Charles University
Harvard University
Mohammed VI Polytechnic University
Université Montpellier 2

Research output: Contribution to journal › Conference article › peer-review

Abstract

Although KM3NeT/ARCA was primarily built to detect high-energy neutrinos from astrophysical sources, it also provides a valuable opportunity to study cosmic rays in the TeV to PeV energy range. This is made possible by the detection of down-going atmospheric muons produced in cosmic-ray air showers, the same particles that usually represent background in neutrino searches. In this study, we focus on identifying large-scale anisotropies in the arrival directions of these cosmic rays, using data from ARCA’s first detection units. To separate true anisotropies signals from instrumental effects, the East-West method, which correctly removes the count variations not associated with real anisotropies, has been applied. The distribution of event counts in 20-minute sidereal time bin is analyzed to search for a dipole component. The amplitude of the first harmonic shows a significance of 1.7 σ, hence, an upper limit on the dipole amplitude at 2.0 × 10⁻³ is set at 99% confidence level.

Original language	English
Article number	202
Journal	Proceedings of Science
Volume	501
DOIs	https://doi.org/10.22323/1.501.0202
Publication status	Published - 30 Dec 2025
Event	39th International Cosmic Ray Conference, ICRC 2025 - Geneva, Switzerland Duration: 15 Jul 2025 → 24 Jul 2025

ASJC Scopus subject areas

Multidisciplinary

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10.22323/1.501.0202

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@article{026dc33cb6774d449de70895d931a562,

title = "Search for Large-Scale Cosmic-Ray Anisotropy with the First Detection Units of KM3NeT/ARCA",

abstract = "Although KM3NeT/ARCA was primarily built to detect high-energy neutrinos from astrophysical sources, it also provides a valuable opportunity to study cosmic rays in the TeV to PeV energy range. This is made possible by the detection of down-going atmospheric muons produced in cosmic-ray air showers, the same particles that usually represent background in neutrino searches. In this study, we focus on identifying large-scale anisotropies in the arrival directions of these cosmic rays, using data from ARCA{\textquoteright}s first detection units. To separate true anisotropies signals from instrumental effects, the East-West method, which correctly removes the count variations not associated with real anisotropies, has been applied. The distribution of event counts in 20-minute sidereal time bin is analyzed to search for a dipole component. The amplitude of the first harmonic shows a significance of 1.7 σ, hence, an upper limit on the dipole amplitude at 2.0 × 10−3 is set at 99\% confidence level.",

author = "\{KM3NeT Collaboration\} and Bouasla, \{Amani Besma\} and Reda Attallah and O. Adriani and A. Albert and Alhebsi, \{A. R.\} and S. Alshalloudi and M. Alshamsi and \{Alves Garre\}, S. and F. Ameli and M. Andre and L. Aphecetche and M. Ardid and S. Ardid and J. Aublin and F. Badaracco and L. Bailly-Salins and B. Baret and A. Bariego-Quintana and M. Barnard and Y. Becherini and M. Bendahman and \{Benfenati Gualandi\}, F. and M. Benhassi and Benoit, \{D. M.\} and Z. Be{\v n}u{\v s}ov{\'a} and E. Berbee and E. Berti and V. Bertin and P. Betti and S. Biagi and M. Boettcher and D. Bonanno and M. Bond{\`i} and S. Bottai and Bouasla, \{A. B.\} and J. Boumaaza and M. Bouta and M. Bouwhuis and C. Bozza and Bozza, \{R. M.\} and H. Br{\^a}nza{\c s} and F. Bretaudeau and M. Breuhaus and R. Bruijn and J. Brunner and R. Bruno and E. Buis and R. Buompane and I. Burriel and S. Razzaque",

note = "Publisher Copyright: {\textcopyright} Copyright owned by the author(s); 39th International Cosmic Ray Conference, ICRC 2025 ; Conference date: 15-07-2025 Through 24-07-2025",

year = "2025",

month = dec,

day = "30",

doi = "10.22323/1.501.0202",

language = "English",

volume = "501",

journal = "Proceedings of Science",

issn = "1824-8039",

publisher = "Sissa Medialab Srl",

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TY - JOUR

T1 - Search for Large-Scale Cosmic-Ray Anisotropy with the First Detection Units of KM3NeT/ARCA

AU - KM3NeT Collaboration

AU - Bouasla, Amani Besma

AU - Attallah, Reda

AU - Adriani, O.

AU - Albert, A.

AU - Alhebsi, A. R.

AU - Alshalloudi, S.

AU - Alshamsi, M.

AU - Alves Garre, S.

AU - Ameli, F.

AU - Andre, M.

AU - Aphecetche, L.

AU - Ardid, M.

AU - Ardid, S.

AU - Aublin, J.

AU - Badaracco, F.

AU - Bailly-Salins, L.

AU - Baret, B.

AU - Bariego-Quintana, A.

AU - Barnard, M.

AU - Becherini, Y.

AU - Bendahman, M.

AU - Benfenati Gualandi, F.

AU - Benhassi, M.

AU - Benoit, D. M.

AU - Beňušová, Z.

AU - Berbee, E.

AU - Berti, E.

AU - Bertin, V.

AU - Betti, P.

AU - Biagi, S.

AU - Boettcher, M.

AU - Bonanno, D.

AU - Bondì, M.

AU - Bottai, S.

AU - Bouasla, A. B.

AU - Boumaaza, J.

AU - Bouta, M.

AU - Bouwhuis, M.

AU - Bozza, C.

AU - Bozza, R. M.

AU - Brânzaş, H.

AU - Bretaudeau, F.

AU - Breuhaus, M.

AU - Bruijn, R.

AU - Brunner, J.

AU - Bruno, R.

AU - Buis, E.

AU - Buompane, R.

AU - Burriel, I.

AU - Razzaque, S.

PY - 2025/12/30

Y1 - 2025/12/30

N2 - Although KM3NeT/ARCA was primarily built to detect high-energy neutrinos from astrophysical sources, it also provides a valuable opportunity to study cosmic rays in the TeV to PeV energy range. This is made possible by the detection of down-going atmospheric muons produced in cosmic-ray air showers, the same particles that usually represent background in neutrino searches. In this study, we focus on identifying large-scale anisotropies in the arrival directions of these cosmic rays, using data from ARCA’s first detection units. To separate true anisotropies signals from instrumental effects, the East-West method, which correctly removes the count variations not associated with real anisotropies, has been applied. The distribution of event counts in 20-minute sidereal time bin is analyzed to search for a dipole component. The amplitude of the first harmonic shows a significance of 1.7 σ, hence, an upper limit on the dipole amplitude at 2.0 × 10−3 is set at 99% confidence level.

AB - Although KM3NeT/ARCA was primarily built to detect high-energy neutrinos from astrophysical sources, it also provides a valuable opportunity to study cosmic rays in the TeV to PeV energy range. This is made possible by the detection of down-going atmospheric muons produced in cosmic-ray air showers, the same particles that usually represent background in neutrino searches. In this study, we focus on identifying large-scale anisotropies in the arrival directions of these cosmic rays, using data from ARCA’s first detection units. To separate true anisotropies signals from instrumental effects, the East-West method, which correctly removes the count variations not associated with real anisotropies, has been applied. The distribution of event counts in 20-minute sidereal time bin is analyzed to search for a dipole component. The amplitude of the first harmonic shows a significance of 1.7 σ, hence, an upper limit on the dipole amplitude at 2.0 × 10−3 is set at 99% confidence level.

UR - https://www.scopus.com/pages/publications/105029023709

U2 - 10.22323/1.501.0202

DO - 10.22323/1.501.0202

M3 - Conference article

AN - SCOPUS:105029023709

SN - 1824-8039

VL - 501

JO - Proceedings of Science

JF - Proceedings of Science

M1 - 202

T2 - 39th International Cosmic Ray Conference, ICRC 2025

Y2 - 15 July 2025 through 24 July 2025

ER -

Search for Large-Scale Cosmic-Ray Anisotropy with the First Detection Units of KM3NeT/ARCA

Abstract

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