papers

Publications (41)

astro-ph.HE2025

The Pierre Auger Observatory: Contributions to the 39th International Cosmic Ray Conference (ICRC 2025)

The Pierre Auger Collaboration, A. Abdul Halim, P. Abreu +352

The Pierre Auger Observatory, located in La Pampa Amarilla, Argentina, has been continuously acquiring data since 2004. It comprises a surface detector array covering 3,000 km

astro-ph.HE2022

A search for photons with energies above eV using hybrid data from the low-energy extensions of the Pierre Auger Observatory

The Pierre Auger Collaboration, P. Abreu, M. Aglietta +373

Ultra-high-energy photons with energies exceeding eV offer a wealth of connections to different aspects of cosmic-ray astrophysics as well as to gamma-ray and neutrino as…

astro-ph.HE2022

Searches for Ultra-High-Energy Photons at the Pierre Auger Observatory

The Pierre Auger Collaboration, P. Abreu, M. Aglietta +362

The Pierre Auger Observatory, being the largest air-shower experiment in the world, offers an unprecedented exposure to neutral particles at the highest energies. Since the start o…

astro-ph.HE2023

AugerPrime Surface Detector Electronics

The Pierre Auger Collaboration, A. Abdul Halim, P. Abreu +368

Operating since 2004, the Pierre Auger Observatory has led to major advances in our understanding of the ultra-high-energy cosmic rays. The latest findings have revealed new insigh…

astro-ph.HE2024

Constraining models for the origin of ultra-high-energy cosmic rays with a novel combined analysis of arrival directions, spectrum, and composition data measured at the Pierre Auger Observatory

The Pierre Auger Collaboration, A. Abdul Halim, P. Abreu +371

The combined fit of the measured energy spectrum and shower maximum depth distributions of ultra-high-energy cosmic rays is known to constrain the parameters of astrophysical model…

astro-ph.HE2022

Arrival Directions of Cosmic Rays above 32 EeV from Phase One of the Pierre Auger Observatory

The Pierre Auger Collaboration, P. Abreu, M. Aglietta +372

A promising energy range to look for angular correlation between cosmic rays of extragalactic origin and their sources is at the highest energies, above few tens of EeV ($1\:{\rm E…

astro-ph.HE2026

Search for ultra-high energy neutrons from Galactic sources with the Pierre Auger Observatory

The Pierre Auger Collaboration, A. Abdul Halim, P. Abreu +357

Deflections in the propagation of charged ultra-high-energy cosmic rays (UHECRs) caused by magnetic fields make the identification of their sources challenging. On the other hand,…

astro-ph.HE2022

Search for Spatial Correlations of Neutrinos with Ultra-High-Energy Cosmic Rays

The ANTARES collaboration, A. Albert, S. Alves +1042

For several decades, the origin of ultra-high-energy cosmic rays (UHECRs) has been an unsolved question of high-energy astrophysics. One approach for solving this puzzle is to corr…

astro-ph.HE2025

Precision cross-sections for advancing cosmic-ray physics and other applications: a comprehensive programme for the next decade

D. Maurin, L. Audouin, E. Berti +32

Cosmic-ray physics in the GeV-to-TeV energy range has entered a precision era thanks to recent data from space-based experiments. However, the poor knowledge of nuclear reactions,…

astro-ph.HE2024

Testing Hadronic-Model Predictions of Depth of Maximum of Air-Shower Profiles and Ground-Particle Signals using Hybrid Data of the Pierre Auger Observatory

The Pierre Auger Collaboration, A. Abdul Halim, P. Abreu +368

We test the predictions of hadronic interaction models regarding the depth of maximum of air-shower profiles, , and ground-particle signals in water-Cherenkov detectors at…

astro-ph.HE2022

Testing effects of Lorentz invariance violation in the propagation of astroparticles with the Pierre Auger Observatory

The Pierre Auger Collaboration, P. Abreu, M. Aglietta +374

Lorentz invariance violation (LIV) is often described by dispersion relations of the form with delta different based on particle type , with…

hep-ex2025

Precision cross-sections for advancing cosmic-ray physics. Input to the 2026 ESPPU from the XSCRC community

S. Mariani, L. Audouin, E. Berti +32

The latest generation of cosmic-ray direct detection experiments is providing a wealth of high-precision data, stimulating a very rich and active debate in the community on the rel…

astro-ph.HE2024

The Pierre Auger Observatory Open Data

The Pierre Auger Collaboration, A. Abdul Halim, P. Abreu +358

The Pierre Auger Collaboration has embraced the concept of open access to their research data since its foundation, with the aim of giving access to the widest possible community.…

physics.space-ph2025

Quasi-constant time gap in multiple rings of elves

The Pierre Auger Collaboration, A. Abdul Halim, P. Abreu +359

We present evidence that the time delay between the multiple rings of elves is not caused by the ground reflection of the electromagnetic pulse produced by intracloud lightning. To…

astro-ph.HE2023

Search for UHE Photons from Gravitational Wave Sources with the Pierre Auger Observatory

The Pierre Auger Collaboration, A. Abdul Halim, P. Abreu +368

A search for time-directional coincidences of ultra-high-energy (UHE) photons above 10 EeV with gravitational wave (GW) events from the LIGO/Virgo runs O1 to O3 is conducted with t…

astro-ph.HE2025

The distribution of ultra-high-energy cosmic rays along the supergalactic plane measured at the Pierre Auger Observatory

The Pierre Auger Collaboration, A. Abdul Halim, P. Abreu +364

Ultra-high-energy cosmic rays are known to be mainly of extragalactic origin, and their propagation is limited by energy losses, so their arrival directions are expected to correla…

astro-ph.HE2026

Depth of Maximum of Air-Shower Profiles above 10^17.7 eV Measured with the Fluorescence Detector of the Pierre Auger Observatory

The Pierre Auger Collaboration, A. Abdul Halim, P. Abreu +358

We present measurements of the depth of shower maximum, Xmax, for cosmic-ray-induced extensive air showers recorded by the fluorescence detector of the Pierre Auger Observatory ove…

hep-ph2024

Constraints on metastable superheavy dark matter coupled to sterile neutrinos with the Pierre Auger Observatory

The Pierre Auger Collaboration, A. Abdul Halim, P. Abreu +368

Dark matter particles could be superheavy, provided their lifetime is much longer than the age of the universe. Using the sensitivity of the Pierre Auger Observatory to ultra-high…

astro-ph.HE2024

Search for photons above 10 eV by simultaneously measuring the atmospheric depth and the muon content of air showers at the Pierre Auger Observatory

The Pierre Auger Collaboration, A. Abdul Halim, P. Abreu +364

The Pierre Auger Observatory is the most sensitive instrument to detect photons with energies above eV. It measures extensive air showers generated by ultra high energy c…

astro-ph.HE2026

Observation of the Moon and Sun shadows with cosmic rays at an average energy of eV

The Pierre Auger Collaboration, A. Abdul Halim, P. Abreu +346

Interactions of cosmic rays with the Moon and the Sun produce deficits in their arrival-direction distributions relative to an isotropic flux. Such shadows have been observed previ…

astro-ph.IM2025

Long-term calibration and validation of stability of the Auger Engineering Radio Array using the diffuse Galactic radio emission

The Pierre Auger Collaboration, A. Abdul Halim, P. Abreu +356

The Auger Engineering Radio Array (AERA) measures radio emission from high-energy extensive air showers. Consisting of 153 autonomous radio-detector stations spread over \,km$^…

astro-ph.HE2026

Measuring the muon content of inclined air showers using AERA and the water-Cherenkov detectors of the Pierre Auger Observatory

The Pierre Auger Collaboration, A. Abdul Halim, P. Abreu +360

We present a novel approach for assessing the muon content of air showers with large zenith angles on a combined analysis of their radio emission and particle footprint. We use the…

astro-ph.HE2022

Investigating Hadronic Interactions at Ultra-High Energies with the Pierre Auger Observatory

Isabel Goos, :, P. Abreu +374

The development of an extensive air shower depends not only on the nature of the primary ultra-high-energy cosmic ray but also on the properties of the hadronic interactions. For e…

astro-ph.HE2025

Search for a diffuse flux of photons with energies above tens of PeV at the Pierre Auger Observatory

The Pierre Auger Collaboration, A. Abdul Halim, P. Abreu +359

Diffuse photons of energy above 0.1 PeV, produced through the interactions between cosmic rays and either interstellar matter or background radiation fields, are powerful tracers o…

astro-ph.HE2025

A search for the anomalous events detected by ANITA using the Pierre Auger Observatory

The Pierre Auger Collaboration, A. Abdul Halim, P. Abreu +374

A dedicated search for upward-going air showers at zenith angles exceeding and energies EeV has been performed using the Fluorescence Detector of the Pierre Aug…

astro-ph.HE2023

Search for photons above 10 eV with the surface detector of the Pierre Auger Observatory

The Pierre Auger Collaboration, P. Abreu, M. Aglietta +365

We use the surface detector of the Pierre Auger Observatory to search for air showers initiated by photons with an energy above eV. Photons in the zenith angle range from…

astro-ph.HE2022

A Catalog of the Highest-Energy Cosmic Rays Recorded During Phase I of Operation of the Pierre Auger Observatory

The Pierre Auger Collaboration, A. Abdul Halim, P. Abreu +376

A catalog containing details of the highest-energy cosmic rays recorded through the detection of extensive air-showers at the Pierre Auger Observatory is presented with the aim of…

astro-ph.HE2023

Constraining the sources of ultra-high-energy cosmic rays across and above the ankle with the spectrum and composition data measured at the Pierre Auger Observatory

The Pierre Auger Collaboration, A. Abdul Halim, P. Abreu +365

In this work we present the interpretation of the energy spectrum and mass composition data as measured by the Pierre Auger Collaboration above eV. We use an ast…

astro-ph.HE2025

Radio Measurements of the Depth of Air-Shower Maximum at the Pierre Auger Observatory

The Pierre Auger Collaboration, A. Abdul Halim, P. Abreu +372

The Auger Engineering Radio Array (AERA), part of the Pierre Auger Observatory, is currently the largest array of radio antenna stations deployed for the detection of cosmic rays,…

astro-ph.IM2023

Ground observations of a space laser for the assessment of its in-orbit performance

The Pierre Auger Collaboration, O. Lux, I. Krisch +380

The wind mission Aeolus of the European Space Agency was a groundbreaking achievement for Earth observation. Between 2018 and 2023, the space-borne lidar instrument ALADIN onboard…

hep-ph2026

Search for active-sterile neutrino transitions using Pierre Auger Observatory data

The Pierre Auger Collaboration, A. Abdul Halim, P. Abreu +348

We investigate the sensitivity of the Pierre Auger Observatory to physics beyond the Standard Model arising from magnetic-moment-induced transitions between active and heavy steril…

hep-ex2026

Proton-air interaction properties at TeV from shower-depth measurements with the Pierre Auger Observatory and their connection to the Muon Puzzle

The Pierre Auger Collaboration, A. Abdul Halim, P. Abreu +347

Hybrid measurements at the Pierre Auger Observatory indicate that most high-energy hadronic interaction models underestimate the average depth of the shower maximum, $\langle X_{\m…

astro-ph.HE2026

Bounds on Lorentz invariance violation from muon fluctuations at the Pierre Auger Observatory

The Pierre Auger Collaboration, A. Abdul Halim, P. Abreu +357

Quantum gravity theories often modify spacetime symmetries. In particular, Lorentz invariance may be violated when approaching the Planck scale. Although the scales at which intera…

astro-ph.HE2025

The Energy Spectrum of Ultra-High Energy Cosmic Rays across Declinations to as measured at the Pierre Auger Observatory

The Pierre Auger Collaboration, A. Abdul Halim, P. Abreu +360

The energy spectrum of cosmic rays above 2.5 EeV has been measured across the declination range using data from events accrued a…

astro-ph.HE2025

Inference of the Mass Composition of Cosmic Rays with energies from to eV using the Pierre Auger Observatory and Deep Learning

The Pierre Auger Collaboration, A. Abdul Halim, P. Abreu +364

We present measurements of the atmospheric depth of the shower maximum , inferred for the first time on an event-by-event level using the Surface Detector of the Pi…

astro-ph.HE2022

Limits to gauge coupling in the dark sector set by the non-observation of instanton-induced decay of Super-Heavy Dark Matter in the Pierre Auger Observatory data

The Pierre Auger Collaboration, P. Abreu, M. Aglietta +374

Instantons, which are non-perturbative solutions to Yang-Mills equations, provide a signal for the occurrence of quantum tunneling between distinct classes of vacua. They can give…

astro-ph.HE2024

Impact of the Magnetic Horizon on the Interpretation of the Pierre Auger Observatory Spectrum and Composition Data

The Pierre Auger Collaboration, A. Abdul Halim, P. Abreu +364

The flux of ultra-high energy cosmic rays reaching Earth above the ankle energy (5 EeV) can be described as a mixture of nuclei injected by extragalactic sources with very hard spe…

astro-ph.HE2022

Cosmological implications of photon-flux upper limits at ultra-high energies in scenarios of Planckian-interacting massive particles for dark matter

The Pierre Auger Collaboration, P. Abreu, M. Aglietta +374

Using the data of the Pierre Auger Observatory, we report on a search for signatures that would be suggestive of super-heavy particles decaying in the Galactic halo. From the lack…

astro-ph.HE2025

Large-scale cosmic ray anisotropies with 19 years of data from the Pierre Auger Observatory

The Pierre Auger Collaboration, A. Abdul Halim, P. Abreu +355

Results are presented for the measurement of large-scale anisotropies in the arrival directions of ultra-high-energy cosmic rays detected at the Pierre Auger Observatory during 19…

astro-ph.HE2025

Measurement of the Depth of Maximum of Air-Shower Profiles with energies between and eV using the Surface Detector of the Pierre Auger Observatory and Deep Learning

The Pierre Auger Collaboration, A. Abdul Halim, P. Abreu +364

We report an investigation of the mass composition of cosmic rays with energies from 3 to 100 EeV (1 EeV= eV) using the distributions of the depth of shower maximum $X_\ma…

astro-ph.HE2025

Demonstrating Agreement between Radio and Fluorescence Measurements of the Depth of Maximum of Extensive Air Showers at the Pierre Auger Observatory

The Pierre Auger Collaboration, A. Abdul Halim, P. Abreu +372

We show, for the first time, radio measurements of the depth of shower maximum () of air showers induced by cosmic rays that are compared to measurements of the estab…