Conveners
Ultra-High Energy Cosmic Rays
- Piera Luisa Ghia (LPNHE-CNRS, Paris)
Ultra-High Energy Cosmic Rays
- Piera Luisa Ghia (LPNHE-CNRS, Paris)
Presentation materials
The two observatories with largest effective areas in the world, Pierre
Auger and Telescope Array have been contiuosly operating for more than
20 years gathering an impressive statistics on cosmic rays with energies
up to above 10^20 eV. I will review the major achievements from these
two Observatoires, with a focus on the similitude between their measurements, in the same time...
Twenty years have passed since the first measurements from the Pierre Auger Observatory (Auger) and the Telescope Array experiment (TA) began to reveal the origin of ultra-high-energy cosmic rays (UHECRs). However, definite conclusions are yet to be made, with tensions between the spectra, mass composition and anisotropy of the two experiments raising additional questions. In this talk, I...
Measurements of the products of UHECR interactions with the Earth's atmosphere, as obtained in Extended Air Shower Experiments and at Very Large Volume Neutrino Telescopes, offer important information concerning hadronic interactions,
which for some aspects overlaps and for many others complements the information extracted by measurements of collisions at man-made accelerators. In this...
A dipole anisotropy in the ultra-high-energy cosmic ray (UHECR) arrival directions, of extragalactic origin, is now firmly established at energies >8 EeV. Furthermore, the UHECR angular power spectrum shows no power at smaller angular scales than the dipole, apart from hints of possible individual hot or warm spots for energy thresholds ≳40 EeV. We model the extragalactic source distribution...
The Pierre Auger Observatory has a public data policy following the FAIR principles (Findable, Accessible, Interoperable, and Reusable). We aim to share the data with the scientific community as part of the multi-messenger effort at different levels and for educational activities to engage the general public. Following the first portal created in 2007, a new portal hosted at...
Extensive air showers initiated by ultra-high-energy cosmic rays are a unique opportunity to probe hadronic interactions in energy and phase-space regions out of the reach of man-made accelerators. The Pierre Auger Observatory, now entering its Phase II with the AugerPrime upgrade, is a multi-hybrid detector capable of extracting numerous shower observables. These observables directly probe...
Diffusion tensor coefficients play a central role in describing cosmic-ray transport in various astrophysical environments permeated with magnetic fields, which are usually modeled as a fluctuating field on top of a mean field. In this article, a formal derivation of these coefficients is presented by means of the calculation of velocity decorrelation functions of particles. It relies mainly...
The Extreme Universe Space Observatory on a Super Pressure Balloon 2 (EUSO-SPB2) mission launched from Wanaka NZ on May 13, 2023 and was terminated about 36h later over the Pacific Ocean due to a leak in the balloon. The payload included two main instruments. The Fluorescence Telescope (FT) pointed in nadir to search for the first Ultra-High Energy Cosmic Ray (UHECR) induced extensive...
In this paper, we conduct a Monte Carlo simulation study to investigate the production of strange and multi-strange hadrons in high-multiplicity proton-proton collisions. Our objective is to refine and validate the hadronic interaction models crucial for air shower simulations such as EPOS, QGSJET, SIBYLL, and PYTHIA. These models play a pivotal role in predicting the propagation of extensive...
