Ultrahigh energy cosmic ray composition from surface air shower and underground muon measurements at Soudan 2

The understanding of the basic properties of the ultrahigh-energy extensive air showers is dependent on the description of hadronic interactions in an energy range beyond that probed by the LHC. One of the uncertainties present in the modeling of air showers is the treatment of diffractive interactions, which are dominated by nonperturbative physics and usually described by phenomenological models. These interactions are expected to affect the development of the air showers, since they provide a way of transporting substantial amounts of energy deep in the atmosphere, modifying the global characteristics of the shower profile. In this paper, we investigate the impact of diffractive interactions in the observables that can be measured in hadronic collisions at high energies and ultrahigh-energy cosmic ray interactions. We consider three distinct phenomenological models for the treatment of diffractive physics and estimate the influence of these interactions on the elasticity, number of secondaries, longitudinal air shower profiles and muon densities for proton-air and iron-air collisions at different primary energies. Our results demonstrate that even for the most recent models, diffractive events have a non-negligible effect on the observables and that the distinct approaches for these interactions, present in the phenomenological models, still are an important source of theoretical uncertainty for the description of the extensive air showers.

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Study of muons from ultrahigh energy cosmic ray air showers measured with the Telescope Array experiment

EPJ Web of Conferences ◽

10.1051/epjconf/201921002012 ◽

2019 ◽

Vol 210 ◽

pp. 02012

Author(s):

R. Takeishi

Keyword(s):

Interaction Model ◽

Cosmic Ray ◽

Mass Composition ◽

Ultrahigh Energy ◽

Air Showers ◽

Hadronic Interaction ◽

Telescope Array ◽

Interaction Models ◽

Air Shower ◽

Number Of Particles

One of the uncertainties in ultrahigh energy cosmic ray (UHECR) observation derives from the hadronic interaction model used for air shower Monte-Carlo (MC) simulations. One may test the hadronic interaction models by comparing the measured number of muons observed at the ground from UHECR induced air showers with the MC prediction. The Telescope Array (TA) is the largest experiment in the northern hemisphere observing UHECR in Utah, USA. It aims to reveal the origin of UHECRs by studying the energy spectrum, mass composition and anisotropy of cosmic rays by utilizing an array of surface detectors (SDs) and fluorescence detectors. We studied muon densities in the UHE extensive air showers by analyzing the signal of TA SD stations for highly inclined showers. On condition that the muons contribute about 65% of the total signal, the number of particles from air showers is typically 1.88 ± 0.08 (stat.) ± 0.42 (syst.) times larger than the MC prediction with the QGSJET II-03 model for proton-induced showers. The same feature was also obtained for other hadronic interaction models, such as QGSJET II-04.

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PeV Emission of the Crab Nebula: Constraints on the Proton Content in Pulsar Wind and Implications

The Astrophysical Journal ◽

10.3847/1538-4357/ac2ba0 ◽

2021 ◽

Vol 922 (2) ◽

pp. 221

Author(s):

Ruo-Yu Liu ◽

Xiang-Yu Wang

Keyword(s):

Energy Content ◽

Crab Nebula ◽

Cosmic Ray ◽

Ultrahigh Energy ◽

Pulsar Wind Nebulae ◽

Air Shower ◽

Pulsar Wind ◽

The Crab Nebula ◽

Pulsar Winds ◽

Cosmic Ray Flux

Abstract Recently, two photons from the Crab Nebula with energy of approximately 1 PeV were detected by the Large High Altitude Air Shower Observatory (LHAASO), opening an ultrahigh-energy window for studying pulsar wind nebulae (PWNe). Remarkably, the LHAASO spectrum at the highest-energy end shows a possible hardening, which could indicate the presence of a new component. A two-component scenario with a main electron component and a secondary proton component has been proposed to explain the whole spectrum of the Crab Nebula, requiring a proton energy of 1046–1047 erg remaining in the present Crab Nebula. In this paper, we study the energy content of relativistic protons in pulsar winds using the LHAASO data of the Crab Nebula, considering the effect of diffusive escape of relativistic protons. Depending on the extent of the escape of relativistic protons, the total energy of protons lost in the pulsar wind could be 10–100 times larger than that remaining in the nebula presently. We find that the current LHAASO data allow up to (10–50)% of the spindown energy of pulsars being converted into relativistic protons. The escaping protons from PWNe could make a considerable contribution to the cosmic-ray flux of 10–100 PeV. We also discuss the leptonic scenario for the possible spectral hardening at PeV energies.

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Earth-Skimming Ultrahigh Energy Tau Neutrinos Simulated with Monte Carlo Method and CONEX Code

Advances in High Energy Physics ◽

10.1155/2021/9987060 ◽

2021 ◽

Vol 2021 ◽

pp. 1-7

Author(s):

Bouzid Boussaha ◽

Tariq Bitam

Keyword(s):

Monte Carlo ◽

Cosmic Ray ◽

High Energy ◽

Tau Lepton ◽

Ultrahigh Energy ◽

Air Shower ◽

Mountain Valley ◽

Tau Neutrinos ◽

Very High Energy ◽

Very High

This paper is aimed at studying the feasibility of building an Earth-skimming cosmic tau neutrinos detector, with the aim of eventually identifying the ideal dimensions of a natural site mountain-valley for the detection of very high energy neutrinos tau range from 1 0 16 eV to 1 0 20 eV , as well as possibly locate one such site in Algeria. First, a Monte Carlo simulation of the neutrino-[mountain] matter interaction as well as the resulting decay of the tau lepton is conducted to determine the optimal dimensions of the mountain as well as the location of the tau decay in the valley. Second, a CORSIKA (COsmic Ray Simulation for KAscade) simulation with the CONEX option is conducted to track the evolution of the almost horizontal air shower initiated by the tau lepton. Many particles are produced, which are part of the shower components: electrons, muons, gammas, pions, etc. The study of the spatial distribution of these particles enables the discovery of the optimal width of the valley, and consequently, the distance at which to lay the detection network.

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ULTRAHIGH ENERGY NEUTRINOS

International Journal of Modern Physics A ◽

10.1142/s0217751x03017385 ◽

2003 ◽

Vol 18 (22) ◽

pp. 4085-4096 ◽

Cited By ~ 2

Author(s):

SHARADA IYER DUTTA ◽

MARY HALL RENO ◽

INA SARCEVIC

Keyword(s):

Black Hole ◽

Standard Model ◽

Cross Section ◽

Neutrino Oscillations ◽

Ultrahigh Energy ◽

Nonstandard Model ◽

Air Shower ◽

Energy Neutrino ◽

The Standard Model ◽

Event Rates

The ultrahigh energy neutrino cross section is well understood in the standard model for neutrino energies up to 1012 GeV, Tests of neutrino oscillations (νμ ↔ ντ) from extragalactic sources of neutrinos are possible with large underground detectors. Measurements of horizontal air shower event rates at neutrino energies above 1010 GeV will be able to constrain nonstandard model contributions to the neutrino-nucleon cross section, e.g., from mini-black hole production.

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