arXiv subjects

Katsuaki Kasahara

Publications and source records attributed to Katsuaki Kasahara.

5 recordsLinked to original sources

arXiv2023

Measurement of the forward $η$ meson production rate in p-p collisions at $\sqrt{s}$=13 TeV with the LHCf-Arm2 detector

The forward $η$ mesons production has been observed by the Large Hadron Collider forward (LHCf) experiment in proton-proton collision at $\sqrt{s}$=13 TeV. This paper presents the measurement of the inclusive production rate of $η$ in $p_T<$ 1.1 GeV/c, expressed as a function of the Feynman-x variable. These results are compared with the predictions of several hadronic interaction models commonly used for the modelling of the air showers produced by ultra-high energy cosmic rays. This is both the first measurement of $η$ mesons from LHCf and the first time a particle containing strange quarks has been observed in the forward region for high-energy collisions. These results will provide a powerful constraint on hadronic interaction models for the purpose of improving the understanding of the processes underlying the air showers produced in the Earth's atmosphere by ultra-energetic cosmic rays.

hep-ex↗

arXiv2021

Simulation study on the effects of diffractive collisions on the prediction of the observables in ultra-high-energy cosmic ray experiments

The mass composition of ultra-high-energy cosmic rays is important for understanding their origin. Owing to our limited knowledge of the hadronic interaction, the interpretations of the mass composition from observations include several open problems, such as the inconsistent interpretations of $\langle X_{\mathrm{max}}\rangle $ and $\langle X_{\mathrm{max}}^μ\rangle $. Futhermore, the large difference between the predictions exists by the hadronic interaction models. Diffractive collision is one of the proposed sources of the uncertainty. In this paper, we discuss the effect of the detailed characteristics of diffractive collisions to the observables of ultra-high-energy cosmic-ray experiments, focusing on three detailed characteristics. These are the cross-sectional fractions of different collision types, diffractive-mass spectrum, and diffractive-mass-dependent particle productions from the diffractive dissociation system. We demonstrated that the current level of the uncertainty in the cross-sectional fraction can affect 8.9 $\mathrm{g/cm^2}$ of $\langle X_{\mathrm{max}}\rangle $ and 9.4 $\mathrm{g/cm^2}$ of $\langle X_{\mathrm{max}}^μ\rangle $, whereas the other details of the diffractive collisions exhibit relatively minor effects.

astro-ph.HE↗

arXiv2013

A comparison study of CORSIKA and COSMOS simulations for extensive air showers

Cosmic rays with energy exceeding ~ 10^{18} eV are referred to as ultra-high energy cosmic rays (UHECRs). Monte Carlo codes for extensive air shower (EAS) simulate the development of EASs initiated by UHECRs in the Earth's atmosphere. Experiments to detect UHECRs utilize EAS simulations to estimate their energy, arrival direction, and composition. In this paper, we compare EAS simulations with two different codes, CORSIKA and COSMOS, presenting quantities including the longitudinal distribution of particles, depth of shower maximum, kinetic energy distribution of particle at the ground, and energy deposited to the air. We then discuss implications of our results to UHECR experiments.

astro-ph.HE↗

arXiv2011

Comparison of CORSIKA and COSMOS simulations

Ultra-high-energy cosmic rays (UHECRs) refer to cosmic rays with energy above 10^{18} eV. UHECR experiments utilize simulations of extensive air shower to estimate the properties of UHECRs. The Telescope Array (TA) experiment employs the Monte Carlo codes of CORSIKA and COSMOS to obtain EAS simulations. In this paper, we compare the results of the simulations obtained from CORSIKA and COSMOS and report differences between them in terms of the longitudinal distribution, Xmax-value, calorimetric energy, and energy spectrum at ground.

astro-ph.HE↗

arXiv2011

Improvement of low energy atmospheric neutrino flux calculation using the JAM nuclear interaction model

We present the calculation of the atmospheric neutrino fluxes with an interaction model named JAM, which is used in PHITS (Particle and Heavy-Ion Transport code System). The JAM interaction model agrees with the HARP experiment a little better than DPMJET-III. After some modifications, it reproduces the muon flux below 1~GeV/c at balloon altitudes better than the modified-DPMJET-III which we used for the calculation of atmospheric neutrino flux in previous works. Some improvements in the calculation of atmospheric neutrino flux are also reported.

astro-ph.HE↗