More Like this

1. Testing the Compatibility of the Depth of the Shower Maximum Measurements performed at Telescope Array and the Pierre Auger Observatory: Auger-TA Mass Composition Working Group Report

   https://doi.org/10.1051/epjconf/202328302008  

   Bergman, Douglas; Bellido, Jose; de Souza, Vitor; Engel, Ralph; Gerber, Zane; Kim, JiHyun; Mayotte, Eric; Tkachenko, Olena; Unger, Michael; Yushkov, Alexey (January 2023, EPJ Web of Conferences)

   De Mitri, I.; Barbato, F.C.T.; Boncioli, D.; Evoli, C.; Pagliaroli, G.; Salamida, F. (Ed.)

   The Telescope Array and the Pierre Auger Observatory estimate the composition of ultra-high-energy cosmic rays by observing the distribution of depths of air-shower maxima, X max . Both experiments directly observe the longitudinal development of air showers using fluorescence telescopes with surface particle detectors used in conjunction to provide precision in determining air-shower geometry. The two experiments differ in the details of the analysis of events, so a direct comparison of X max distributions is not possible. The Auger – Telescope Array Composition Working Group presents their results from a technique to compare X max measurements from Auger with those of Telescope Array. In particular, the compatibility of the first two moments of the X max distributions of Auger with the data from the Black Rock Mesa and Long Ridge detectors of the Telescope Array is tested for energies above 10 18.2 eV. Quantitative comparisons are obtained using air-shower simulations of four representative species made using the Sibyll 2.3d high-energy interaction model. These are weighted to fit the fractional composition seen in Auger data and reconstructed using the Telescope Array detector response and analysis methods. 

   more » « less
2. Direct measurement of the muonic content of extensive air showers between $$\mathbf { 2\times 10^{17}}$$ and $$\mathbf {2\times 10^{18}}~$$eV at the Pierre Auger Observatory

   https://doi.org/10.1140/epjc/s10052-020-8055-y  

   Aab, A.; Abreu, P.; Aglietta, M.; Albury, J. M.; Allekotte, I.; Almela, A.; Alvarez Castillo, J.; Alvarez-Muñiz, J.; Anastasi, G. A.; Anchordoqui, L.; et al (August 2020, The European Physical Journal C)

   null (Ed.)

   Abstract The hybrid design of the Pierre Auger Observatory allows for the measurement of the properties of extensive air showers initiated by ultra-high energy cosmic rays with unprecedented precision. By using an array of prototype underground muon detectors, we have performed the first direct measurement, by the Auger Collaboration, of the muon content of air showers between $$2\times 10^{17}$$ 2 × 10 17 and $$2\times 10^{18}$$ 2 × 10 18 eV. We have studied the energy evolution of the attenuation-corrected muon density, and compared it to predictions from air shower simulations. The observed densities are found to be larger than those predicted by models. We quantify this discrepancy by combining the measurements from the muon detector with those from the Auger fluorescence detector at $$10^{{17.5}}\, {\mathrm{eV}} $$ 10 17.5 eV and $$10^{{18}}\, {\mathrm{eV}} $$ 10 18 eV . We find that, for the models to explain the data, an increase in the muon density of $$38\%$$ 38 % $$\pm 4\% (12\%)$$ ± 4 % ( 12 % ) $$\pm {}^{21\%}_{18\%}$$ ± 18 % 21 % for EPOS-LHC , and of $$50\% (53\%)$$ 50 % ( 53 % ) $$\pm 4\% (13\%)$$ ± 4 % ( 13 % ) $$\pm {}^{23\%}_{20\%}$$ ± 20 % 23 % for QGSJetII-04 , is respectively needed. 

   more » « less
3. Radio detection of ultrahigh-energy cosmic-ray air showers

   https://doi.org/10.1140/epjs/s11734-025-01503-4  

   Schröder, Frank_G (February 2025, The European Physical Journal Special Topics)

   Abstract Radio antennas have become a standard tool for the detection of cosmic-ray air showers in the energy range above$$10^{16}\,$$ ${10}^{16}$eV. The radio signal of these air showers is generated mostly due to the deflection of electrons and positrons in the geomagnetic field, and contains information about the energy and the depth of the maximum of the air showers. Unlike the traditional air-Cherenkov and air-fluorescence techniques for the electromagnetic shower component, radio detection is not restricted to clear nights, and recent experiments have demonstrated that the measurement accuracy can compete with these traditional techniques. Numerous particle detector arrays for air showers have thus been or will be complemented by radio antennas. In particular when combined with muon detectors, the complementary information provided by the radio antennas can enhance the total accuracy for the arrival direction, energy and mass of the primary cosmic rays. Digitization and computational techniques have been crucial for this recent progress, and radio detection will play an important role in next-generation experiments for ultrahigh-energy cosmic rays. Moreover, stand-alone radio experiments are under development and will search for ultrahigh-energy photons and neutrinos in addition to cosmic rays. This article provides a brief introduction to the physics of the radio emission of air showers, an overview of air-shower observatories using radio antennas, and highlights some of their recent results. 

   more » « less
4. Cosmic ray measurements with IceCube and IceTop

   https://doi.org/10.21468/SciPostPhysProc.13.002  

   Soldin, Dennis (January 2023, SciPost Physics Proceedings)

   IceCube is a cubic-kilometer Cherenkov detector in the deep ice at the geographic South Pole. The dominant event yield in the deep ice detector consists of penetrating atmospheric muons with energies above approximately 300 GeV, produced in cosmic ray air showers. In addition, the surface array, IceTop, measures the electromagnetic component and GeV muons of air showers. Hence, IceCube and IceTop yield unique opportunities to study cosmic rays with unprecedented statistics in great detail. We will present recent results of comic ray measurements from IceCube and IceTop. In this overview, we will highlight measurements of the energy spectrum of cosmic rays from 250 TeV up to the EeV range and their mass composition above 3 PeV. We will also report recent results from measurements of the muon content in air showers and discuss their consistency with predictions from current hadronic interaction models. 

   more » « less
5. Latest Cosmic Ray Results from IceTop and IceCube

   https://doi.org/10.1051/epjconf/201921003005  

   Andeen, Karen; Plum, Matthias; Lhenry-Yvon, I.; Biteau, J.; Deligny, O.; Ghia, P. (January 2019, EPJ Web of Conferences)

   The IceCube Neutrino Observatory at the geographic South Pole, with its surface array IceTop, detects three different components of extensive air showers: the total signal at the surface, low energy muons on the periphery of the showers, and high energy muons in the deep In Ice array of IceCube. These measurements enable determination of the energy spectrum and composition of cosmic rays from PeV to EeV energies, the anisotropy in the distribution of cosmic ray arrival directions, the muon density of cosmic ray air showers, and the PeV gamma-ray flux. Furthermore, IceTop can be used as a veto for the neutrino measurements. The latest results from these IceTop analyses will be presented along with future plans. 

   more » « less