Electrons In Extensive Air Showers Research Articles

Results of the Further Analysis of Data from the Tien Shan Array in the Energy Spectrum of Primary Cosmic Rays in the Energy Range of $${2\times 10^{13}{-}3\times 10^{17}}$$ eV

The energy spectrum of primary cosmic rays at energies between at 2x10$^{13}$ - 3x10$^{17}$ eV is presented according to data from the Tien Shan array on the basis of the detection of the number of electrons in extensive air showers. In the energy range 5x10$^{15}$ - 3x10$^{17}$ eV, the spectrum was obtained by means of the HADRON array and was extended to the region of lower energies from 2x10$^{13}$ eV on the basis of the results of an individual experiment. The changes in the slope of the spectrum in the energy range of 10$^{16}$ - 3x10$^{17}$ eV and a feature of this spectrum at about 1017 eV are analyzed in detail and are described. The spectrum in question is compared with the results obtained at some other arrays.

Model-stable universality of the air shower electromagnetic component: An approach to solving the mass composition problem

On the basis of the scaling approach and CORSIKA simulations data the radial scale factor of lateral distribution of electrons in extensive air showers is confirmed as potentially effective primary mass estimator, and its sensitivity to hadronic interaction model is investigated. It is shown that improved composition results both on average and event-by-event basis can be achieved taking into account the universality property of air shower development expressed by the relation between radial scale factor and longitudinal age parameter. The enhancements of such a theoretically motivated tool for the unbiased cosmic ray composition deduction in a wide primary energy range from (multi-)hybrid air shower measurements of nearest future are discussed.

Model-stable universality of the air shower electromagnetic component: An approach to solving the mass composition problem

On the basis of the scaling approach and CORSIKA simulations data the radial scale factor of the lateral distribution of electrons in extensive air showers is confirmed as a potentially effective primary mass estimator, and its sensitivity to hadronic interaction model is investigated. It is shown that improved composition results both on average and event-by-event basis can be achieved taking into account the universality property of air shower development expressed by the relation between the radial scale factor and the longitudinal age parameter. The enhancements of such a theoretically motivated tool for an unbiased cosmic ray composition deduction in a wide primary energy range for current and future (multi-)hybrid air shower measurements are discussed.

Correlation of angular and lateral distributions of electrons in extensive air showers

The aim of this paper is to explain the weak correlation of the angular and lateral deflections of electrons in extensive air showers in the primary energy range 1016–1019 eV, when compared with that in some models of electron propagation. We derive analytical formulae for the correlation coefficient in the multiple scattering model with energy losses and show a strong role of the ionisation in diminishing the correlation. By considering a Heitler-like model of an electromagnetic cascade we show also that the presence of photons, parent to electrons, causes a decrease of the correlation, roughly explaining quantitatively the small correlation in air showers.

Model-independent approach to deducing the mass composition of primary cosmic rays on the basis of the scale invariance in the radial distribution of electrons in extensive air showers

A new approach to deducing the mass composition of primary cosmic rays is proposed using the air showers universality and the scaling property of the electron lateral distribution function. Experimental data from the KASCADE, MSU, and KASCADE-Grande arrays have been analyzed, allowing conclusions as to the variations of mass composition above the knee to be drawn independently of the hadron-nucleus interaction model.

On the fluctuations of the fluorescence photon yield of electrons in extensive air showers for different atmospheric conditions

The air fluorescence technique has long been used to detect extensive air showers and to reconstruct its geometry and energy. The fluorescence photon yield of an electron in air is of main importance in the reconstruction procedure. Several experiments are trying to measure in detail the dependency of the yield with energy. In this work we discuss the calculation of the fluorescence yield convoluted with the energy spectrum of particles in the shower as a function of age. We study the fluctuations of the yield resultant from different atmospheric conditions. We calculate the fluorescence yield as a function of height for the US Standard model and for the winter and summer conditions of the Auger Observatory in Argentine. Using the relation between average X max and energy we calculate the fluctuations between winter and summer seasons as a function of energy for proton and iron nuclei as primary particles. The influences of this fluctuation in the energy error as a function of energy are also discussed.

Lateral distribution of electrons in EAS at superhigh energies: predictions and experimental data

In this paper we present a new approximation for the lateral distribution function of electrons in extensive air showers based on the scaling property established in our recent works. The detailed comparisons of theoretical predictions for the lateral distribution of charged particles in EAS at superhigh energies obtained with the use of new LDF of electrons with the experimental data of AGASA and Yakutsk array are carried out. The influence of the scintillation detector response and the atmospheric temperature effect on the shape of the lateral distribution of electrons is discussed in brief.

Lateral distribution of electrons in air showers

We investigate the lateral distribution of electrons in extensive air showers generated by 10 5 ÷10 9 GeV protons. It was found that the lateral distribution function in extensive air showers contains the same invariant part as the one in a pure electromagnetic cascade. This scaling property is poorly sensitive to the variation of basic. parameters of the hadron-nucleus interactions model. We also report on some initial results obtained for the description of the transition effect of shower particles within scintillators of different thickness.

A new lateral distribution function for electrons in extensive air showers (EAS) detected near sea level

A detailed analysis of Extensive Air Showers in the size range 104–106 particles detected near sea level has yielded a new distribution function for the radial distribution of EAS electrons. The goodness-of-fit criteria applied to the present and already existing similar distribution functions confirm that the present function is appropriate in EAS at radial distances beyond 20 m from the shower axis.

Can the HADRON experiment results at 2*103-2*104 TeV be explained in the quark-gluon string model?

The MQ1 generator of h14N interactions based on the quark-gluon string model has been applied to simulations of cosmic ray cascades in the atmosphere which produce events consisting of gamma -rays and electrons of energy higher than 2 TeV (so-called gamma -families) accompanied by extensive air showers (EAS). Such events were detected by the HADRON experiment (Tian-Shan, 700 g cm-2) installation consisting of emulsion chambers and the EASarray. The detection of a gamma -family in the emulsion chamber was also simulated. Correlations of the calculated gamma -family characteristics and the total number Ne of electrons in EAS were studied and a comparison of these characteristics and the experimental data was performed. There were peculiarities in the simulated families similar to the experimental ones and they can be explained by cascade fluctuations. There were no discrepancies between the experimental data and the MQ1 generator predictions, which assumes an increasing ktot(E). An attempt to select the events produced by primary light nuclei by use of various correlations of gamma -family characteristics and Ne failed. However, by also taking into consideration low-energy muons detected in this experiment it is possible to succeed.

The lateral distribution of electrons in extensive air showers

The lateral distribution of electrons in extensive air showers

The lateral distribution of electrons in extensive air showers

Presents new results of an analysis of the lateral distribution of electrons in extensive air showers. It is shown from experimental data that the lateral distribution of electrons is steeper than the NKG function but not as steep as the function proposed by Lagutin et al. (1979). The author also deduces from the experimental measurements a structure function which yields an age parameter which is consistent with the longitudinal stage of shower development.

Longitudinal development of air-shower electrons studied from the arrival time distributions of atmospheric Cerenkov light measured at 900 m above sea level

The longitudinal development of electrons in extensive air showers around and after the maximum has been studied by measuring the arrival time distributions of atmospheric Cerenkov light from air showers, with primary energies in the range 5*1015 to 2*1017 eV, in the Akeno air-shower array. These arrival time distributions are consistent with those calculated for slow shower development, as would be expected from a model with low multiplicity of particle interactions, as well as for very fast development before the maximum expected from a model with very high multiplicity combined with slow development after the maximum. This implies that the arrival time distributions measured at a low altitude in practice do not lead to a unique solution to the question of the longitudinal development of the shower through the atmosphere. The variation of the mean depth of the maximum development with electron size has also been determined from the arrival time distributions. The comparison with depths calculated from various models of particle interactions suggests the absence of any appreciable changes in the nuclear composition of primary cosmic rays and the character of particle interactions between 5*1015 and 2*1017 eV.

Search for Long-Lived Massive Particles and Time Structure of Electrons in Extensive Air Showers

An experiment to observe accompanied showers delayed relative to the bulk of extensive-air-shower particles near the core was carried out by using plural detectors set at separate places. Four delayed events hitting two or more detectors at the same time were observed. It is difficult to explain these events by accidental coincidence or conventional processes. However, these events can be explained, provided that a parent particle producing the delayed shower has a lifetime of the order of 1 ×10 -6 s and is heavier than a nucleon. The thickness of air shower disk was also measured at core distances less than 50 m.

On delays of particles in extensive air showers

Some features of the temporal distribution of the electrons in extensive air showers by means of the diffusion equations (Landau equations) in theA approximation are considered. The results are compared with data from experiments and Monte Carlo calculations.

Zur longitudinalen Verteilung der Elektronen in gro�en Luftschauern

The standard deviationσ of the instantaneous distribution of electrons in extensive air showers at sea level has been measured by coincidence of two spark counters, a cloud chamber providing data on arrival directions and particle densities. The values published up to now were in the range 2<σ<8 ns and the standard time deviationσ 0 due to instrumental fluctuations was about 4 ns. In this experiment with aσ 0=1,8 ns mean delaysσ have been obtained between 1 and 2 ns, the values decreasing with increasing particle density. This tendency may be due to the fact that the mean separations of the electrons, taken perpendicular to the shower front, are increasing with distance from the shower axis. The fractional contribution of showers within a given range of sizes, the axes of which came down within a given interval of distances from the counters has been calculated. It was concluded that 80% of the showers triggering the two counters were in the range from 105 to 107 particles. By means of these calculations, using the measured values for the mean delaysσ at different particle densities, a simple curve has been constructed which gives the mean separations of electrons vs distance from the shower axis up to 1000 m and is in good agreement with the experimental data ofLinsley andScarsi for great distances from the shower axis.