Related papers: Muon puzzle in ultra-high energy EASs according to…
The origin and nature of ultra high energy cosmic rays remains being a mystery. However, great progress has been made in recent years due to the observations performed by the Pierre Auger Observatory and Telescope Array. In particular, it…
Several methods developed within the Pierre Auger Collaboration for the estimation of the muonic component of the Extensive Air Showers observed in the surface Cherenkov detectors are described. The results derived from the data show a…
We present a new design for the water Cherenkov detectors that are in use in various cosmic ray observatories. This novel design can provide a significant improvement in the independent measurement of the muonic and electromagnetic…
The primary cosmic rays particles with energies above 10**20 eV have been observed at many extensive air shower arrays since the beginning of observations over 40 years ago. The validity of measurements of signal s(600) used as energy…
The Yakutsk array dataset in the energy interval $(10^{17},10^{19})$ eV is revisited in order to interpret the zenith angle distribution of an extensive air shower event rate of ultra-high energy cosmic rays. The close relation of the…
The data of cosmic ray NEVOD-DECOR experiment on the investigation of inclined muon bundles for a long time period (May 2012 - March 2021) are presented. The analysis showed that the observed intensity of muon bundles at primary cosmic ray…
Arrival directions of extensive air showers by using world data are considered. It is shown that distributions of showers in zenith angle at E>10^{19}eV and E>4.10^{19}eV differ from each other. On this basis the conclusions are made: the…
Although the origin of ultra high energy cosmic rays is still unknown, significant progress has been achieved in last decades with the construction of large arrays that are currently taking data. One of the most important pieces of…
The arrival directions of ultrahigh energy extensive air showers (EAS) by Yakutsk, AGASA, P. Auger array data are analyzed. For the first time, the maps of equal exposition of celestial sphere for the distribution of particles by AGASA and…
We present results of horizontal EAS simulations focused on the opportunity of measuring Cherenkov light from air showers at stratospheric balloon altitude (eg. EUSO-SPB2). For a 1 m2 UV light detector at a 38 km altitude, the largest…
We present a meta-analysis of recent muon density measurements made by eight air shower experiments which cover shower energies ranging from PeV to tens of EeV regarding the muon puzzle in extensive air showers. Some experimental analyses…
We present the interpretation of the muon and scintillation signals of ultra-high-energy air showers observed by AGASA and Yakutsk extensive air shower array experiments. We consider case-by-case ten highest energy events with known muon…
Arrival directions of cosmic rays with the energy E>4.10^{19} eV are analyzed by using data of the Yakutsk and AGASA (Japan) extensive air showers (EAS) arrays. It is supposed that the clusters can be formed as a result of decay of…
The muonic and electromagnetic components of air showers are sensitive to the mass of the primary cosmic particle. The sizes of the components can be measured with particle detectors on ground, and the electromagnetic component in addition…
An analysis of calibrations of extensive air showers with zenith angles $\theta \le 50^{\circ}$ and energies $E_{\text{SD}} \ge 10^{18.5}$ eV was carried out in experiments at the Yakutsk array and Telescope Array. The values of…
Ground based observations appear to indicate that Ultra High Energy Cosmic Rays (UHECR) of the highest energies (>10^{18.7} eV) consist of heavy particles -- shower depth and muon production data both pointing towards this conclusion. On…
We present results of an improved analysis of the experimental data of the EAS Cherenkov array Tunka-25. A new function to fit the Cherenkov light lateral distribution LDF at core distances from 0 to 350 m has been developed on the base of…
We report a first measurement for ultra-high energy cosmic rays of the correlation between the depth of shower maximum and the signal in the water Cherenkov stations of air-showers registered simultaneously by the fluorescence and the…
The final analysis of the Extensive Air Shower (EAS) maximum X_max depth distribution derived from the data of Tunka-25 atmospheric Cherenkov light array in the energy range 3.10^15 - 3.10^16 eV is presented. The perspectives of X_max…
Several methods can be used to perform statistical inference of primary composition of cosmic rays measured with water Cerenkov detectors as those in use at the Pierre Auger Southern Observatory. In the present work we assess the impact of…