The recent results of the very precise measurements of the primary cosmic protons and helium nuclei energy spectra by AMS-02 and some rather accurate estimates of these energy spectra generated in ...SNR allow us to elaborate the new approximation of the pimary nucleon energy spectra. As the acuracy of this approximation is rather high we can use it to test various models of hadronic interactions with the help of atmospheric muon energy spectra. The atmospheric vertical muon energy spectra have been calcullated in terms of the EPOS LHC, QGSJET01, QGSJETII-03 and QGSJETII-04 models in the energy range 102 ÷ 105 GeV with help of the CORSIKA package and this new approximation of the primary nucleon spectrum. The comparison of calculations with the muon spectra observed by collaborations L3+Cosmic, LVD and MACRO has shown that all models predict approximately two times lower intensity of the muon energy spectra. As these muons are products of decays of the most energetic π± and K± mesons in the atmosphere, we can conclude that production of these π± and K± mesons is underestimated by EPOS LHC, QGSJET01, QGSJETII-03 and QGSJETII-04 models.
Uncertainties of the model energy spectra of the most energetic secondary charged mesons are discussed. Computer simulations of the partial energy spectra of the atmospheric vertical muons induced by ...primary cosmic particles with various fixed energies in terms of hadronic interactions models had been carried out with the help of the CORSIKA package. These partial spectra have been convolved with the contemporary spectra of the primary cosmic particles in the energy range 0.1-10 000 TeV. Results of simulations are compared with the contemporary data of the atmospheric vertical muon flux. Comparison shows that all models underestimate the production of secondary charged π
±
-mesons (and K
±
-mesons) by a factor of ~ 1.4 ÷ 2 at the highest energies. This underestimation induces a more rapid development of extensive air showers in the atmosphere and results in uncertainties in estimates of energy and composition of the primary cosmic particles.
Fluctuations of lateral distributions of signals in the surface scintillation detectors of the Yakutsk array are found to be large. New estimates of the inclined shower energy had been suggested. In ...view of these estimates the Yakutsk energy spectrum becomes quite comparable with the spectra observed at the Pierre Auger Observatory and the Telescope Array. The shower energy calculated using the data of only one detector may be overestimated if fluctuations are neglected.
A new method has been proposed for estimating the energy of inclined extensive air showers from signals of ground-based scintillation detectors of the Yakutsk extensive air shower array that are ...located at a distance of 600 m from the shower axis in the plane of the array and from the calculations of these signals within two hadron interaction models. New estimates of the energy have been obtained for 116 showers detected in different years. It has been shown that the energy spectra of particles of primary cosmic radiation measured at the Yakutsk array are in agreement with world data.
An original method for calculating the spectrum of atmospheric muons with the aid of the CORSIKA 7.4 code package and numerical integration is proposed. The first step consists in calculating the ...energy distribution of muons for various fixed energies of primary-cosmic-ray particles and within several chosen hadron-interaction models included in the CORSIKA 7.4 code package. After that, the spectrum of atmospheric muons is calculated via integrating the resulting distribution densities with the chosen spectrum of primary-cosmic-ray particles. The atmospheric-muon fluxes that were calculated on the basis of the SIBYLL 2.1, QGSJET01, and QGSJET II-04 models exceed the predictions of the wellknown Gaisser approximation of this spectrum by a factor of 1.5 to 1.8 in the range of muon energies between about 10
3
and 10
4
GeV.Under the assumption that, in the region of extremely highmuon energies, a dominant contribution to the muon flux comes from one to two generations of charged π
±
and
K
±
mesons, the production rate calculated for these mesons is overestimated by a factor of 1.3 to 1.5. This conclusion is confirmed by the results of the LHCf and TOTEM experiments.
A simple method of the vertical muon energy spectrum simulations has been suggested. These calculations have been carried out in terms of various models of hadronic interactions. The most energetic ...π±-mesons and K±-mesons produced in hadron interactions contribute mainly to this energy spectrum of muons due to the very steep energy spectrum of the primary particles. So, some constraints on the hadronic interaction models may be set from a comparison of calculated results with cosmic data on the vertical muon energy spectrum. This comparison showed that the most energetic secondary particles production is too high in the case of the QGSJET II-04 model and rather low in the case of the QGSJET II-03 model. These conclusion have been supported by the LHC data.
New formulas for estimating the energy of inclined extensive air showers (EASs) on the basis of signals in detectors by means of an original method and detailed tables of signals induced in ...scintillation detectors by photons, electrons, positrons, and muons and calculated with the aid of the GEANT4 code package were proposed in terms of the QGSJETII-04, EPOS LHC, and GHEISHA models. The parameters appearing in the proposed formulas were calculated by employing the CORSIKA code package. It is shown that, for showers of zenith angles in the range of 20◦–45◦, the standard constant-intensity-cut method, which is used to interpret data from the Yakutsk EAS array, overestimates the shower energy by a factor of 1.2 to 1.5. It is proposed to employ the calculated VEM (Vertical Equivalent Muon) signal units of 10.8 and 11.4 MeV for, respectively, ground-based and underground scintillation detectors and to take into account the dependence of signals on the azimuthal angle of the detector position and fluctuations in the development of showers.
There is description of the development of detectors for neutrons, based on polystyrene and cadmium layers. Cadmium is used as neutron's converters via reaction (n,γ) and polystyrene is used as ...scintillation material to register the originated gamma quanta. The simulation and experimental investigations of proposed detectors design are presented. The main advantages of proposed detection are short measurement time - approximately 5 µsec. It is shown that the principle, suggested in the models, can be applied to the detection of neutrons from a pulsed neutron source, for example, secondary neutrons, generated by hadron showers in the space environment or by high-intensity pulsed sources based on accelerators. Detection efficiency for the 24*20 cm2 size detector model, measured during the experiment and simulated by the Monte Carlo technique is about 1% with the measurement time being approximately 5 µsec
It is proposed that the energy of inclined extensive air showers be estimated using signals from the surface scintillation detectors of the Yakutsk array, located at a distance of 600 m from the ...shower axis and the zenith angle of shower arrival. Estimates of the energy of inclined showers are calculated using new formulas obtained from simulations using different models of hadron interaction. These models of hadron interaction are validated by comparing calculated and experimental spectra of atmospheric muons. It is found that the muon spectrum calculated with the EPOS LHC and QGSJETII-04 models differs little from the experimental spectrum. It is shown for the first time that the energy spectrum of primary cosmic radiation is in good agreement with the literature data.
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