O. D. Dalkarov

New complex EAS installation of the Tien Shan mountain cosmic ray station

In this paper we present a description of the new complex installation for the study of extensive air showers which was created at the Tien Shan mountain cosmic ray station, as well as the results of the test measurements made there in 2014-2016. At present, the system for registration of electromagnetic shower component consists of ∼100 detector points built on the basis of plastic scintillator plates with the sensitive area of 0.25m2 and 1m2, spread equidistantly over ∼104 m2 space. The dynamic range of scintillation amplitude measurements is currently about (3 − 7) · 104, and there is a prospect of it being extended up to ∼106. The direction of shower arrival is defined by signal delays from a number of the scintillators placed cross-wise at the periphery of the detector system. For the investigation of nuclear active shower components there was created a multi-tier 55m2 ionization-neutron calorimeter with a sum absorber thickness of ∼1000g/cm2, typical spatial resolution of the order of 10cm, and dynamic range of ionization measurement channel about ∼105. Also, the use of saturation-free neutron detectors is anticipated for registration of the highand lowenergy hadron components in the region of shower core. A complex of underground detectors is designed for the study of muonic and penetrative nuclear-active components of the shower. The full stack of data acquisition, detector calibration, and shower parameters restoration procedures are now completed, and the newly obtained shower size spectrum and lateral distribution of shower particles occur in agreement with conventional data. Future studies in the field of 1014 − 1017eV cosmic ray physics to be held at the new shower installation are discussed.

Study of DD-reaction yields from the Ti/TiO2:Dx heterostructure at low energies using the GELIS setup

The results of measurements of the DD-reaction yields from the Ti/TiO2:Dx heterostructure in the energy range of 10–25 keV are presented. Neutron and proton fluxes were measured using a neutron detector based on He-3 counters and a CR-39 plastic track detector. A comparison with calculations showed the existence of significant effects of DD-reaction yield amplification. The screening potential for this heterostructure under these experimental conditions was estimated to be in the range Ue = 160–750 eV.

Low-energy nuclear reactions in crystal structures

Results of studying low-energy nuclear reactions at the HELIS facility (LPI) are presented. Investigations of yields from DD reactions in deuterated crystal structures at deuteron energies of 10 to 25 keV show a considerable enhancement effect. It is shown that exposure of the deuterated targets to the Н+ (proton) and Ne+ beams with energies from 10 to 25 keV and an X-ray beam with the energy of 20 to 30 keV stimulates DD reaction yields. For the CVD diamond target, it is shown that its orientation with respect to the deuteron beam affects the neutron yield. The D+ beam is shown to cause much higher heat release in the TiDx target than the Н+ and Ne+ beams, and this heat release depends on the deuterium concentration in the target and the current density of the deuteron beam.

X-ray spectra from deuterated crystal structures interacting with ion beams with energies below 25 keV

The yields of nuclear reactions in textured CVD (chemical vapor deposition) diamond samples irradiated with a deuteron ion beam are measured. The sample orientation in the deuteron beam is shown to influence the value of the DD reaction yield. The X-ray fluorescence spectra from the surface of deuterated targets irradiated with an ion beam are studied. Analysis of the fluorescence spectra revealed “additional” peaks which cannot be associated with any known elements and require separate studies.

Horizon-T experiment status

Horizon-T is an innovative detector system constructed to study Extensive Air Showers (EAS) in the energy range above 1016 eV coming from a wide range of zenith angles (0o–85o). The system is located at the Tien Shan High-altitude Science Station of the Lebedev Physical Institute of the Russian Academy of Sciences at ∼ 3340 meters above sea level. It consists of eight charged particle detection points separated by distances up to one kilometer as well as an optical detector subsystem to measure the Vavilov-Cherenkov light from the EAS. The time resolution of charged particles and Vavilov-Cherenkov light photons passage of the detector system is a few ns. This level of resolution allows conducting a research of the atmospheric development of individual EAS. This report focuses on a general description of the detector system and the individual sub-systems providing an overview of the operations and latest results.

Distance measurements of the process of the passage of astroparticles with energies above 1015eV through the Earth’s atmosphere

The possibility of studying the interaction of high-energy astroparticles, using the fiber optic technique is considered.