arXiv subjects

Frank Schroeder

Publications and source records attributed to Frank Schroeder.

4 recordsLinked to original sources

arXiv2026

NASA ASTRA Initiative White Paper: Space-Based Mission for Ultrahigh Energy Particles

Ultra-high-energy cosmic rays ($E_{\rm CR} \gtrsim 1$ EeV) are the highest-energy particles known, signaling extreme particle processes at work in the universe. However, many aspects of their nature remain largely unknown, even after more than a century of study. Very-high-energy ($E_ν\gtrsim 1$ PeV neutrinos associated with cosmic-ray interactions, both during the acceleration process and propagation, would provide new insight into these extreme particles, as we have seen at lower energies with the dawn of TeV neutrino astronomy. Nevertheless, only a handful of such neutrinos have been observed thus far. A space-based observatory dedicated to studying cosmic rays, neutrinos, and photons would provide an unprecedented platform for observations of these extreme-energy messengers.

astro-ph.IM↗

arXiv2025

Sensitivity of seasonal variations of the muon energy spectrum in air showers to hadronic interaction models and the cosmic-ray mass composition

The energy spectrum of muons produced in air showers depends not only on the properties of the primary particle, but also on the atmosphere. This is because of the competition between decay and interaction of the parent mesons, which depends on the atmospheric density. As a result, the number of muons at ground shows a seasonal variation, with the strength of the variation depending on the primary cosmic-ray energy, mass, as well as the energy of the detected muons. In this contribution, we study the variations of the muon energy spectrum in air showers using MCEq, a numerical solver of the cascade equations. In particular, we show how the amplitude of the seasonal variations of the number of high-energy (O(TeV)) muons in the shower depends on the primary energy, mass, as well as the assumed hadronic interaction model. A measurement of these variations is possible with the combination of a surface air-shower array and a deep underground detector, which provide a simultaneous measurement of the primary energy and the high-energy muon multiplicity, and may provide a new way to probe the cosmic-ray mass composition and hadronic interactions.

astro-ph.HE↗

arXiv2025

Plans for a new array of radio antennas for the detection of air showers at the 433m surface-detector array of the Pierre Auger Observatory

We present the design and science case for a new array of radio antennas to be located at the Pierre Auger Observatory. Six stations of three SKALA antennas each will be deployed around a single water-Cherenkov surface detector triggering the radio readout. The planned antenna layout will allow for the detection of cosmic rays above a few tens of PeV and reach full efficiency for vertical air showers at several hundred PeV in primary energy. The array will thus be a pathfinder to demonstrate that fully-efficient radio detection in combination with the underground muon detectors already present at the location is possible. This will enable combined studies of the muon component and the depth of shower maximum, relevant for hadronic interaction models studies and more accurate determination of the cosmic-ray mass composition in the energy range of the Galactic-to-extragalactic transition.

astro-ph.HE↗

arXiv2020

Self-consistent approach for measuring the energy spectra and composition of cosmic rays and determining the properties of hadronic interactions at high energy

Air showers, produced by the interaction of energetic cosmic rays with the atmosphere, are an excellent alternative to study particle physics at energies beyond any human-made particle accelerator. For that, it is necessary to identify first the mass composition of the primary cosmic ray (and its energy). None of the existing high energy interaction models have been able to reproduce coherently all air shower observables over the entire energy and zenith angle phase space. This is despite having tried all possible combinations for the cosmic ray mass composition. This proposal outlines a self-consistent strategy to study high energy particle interactions and identify the energy spectra and mass composition of cosmic rays. This strategy involves the participation of different particle accelerators and astrophysics experiments. This is important to cover the entire cosmic ray energy range and a larger phase-space of shower observables to probe the high energy interaction models.

astro-ph.HE↗