[en] Preliminary results of the ²²²Rn content in air and water at the Baksan Neutrino Observatory area are presented. The method of the ²²²Rn extraction from the air and water samples is described

No abstract available

[en] The surface alpha activity of different materials was measured with proportional counters having cathodes of the materials investigated. No materials without alpha activity were found. Semiconductor silicon contains the least activity among the materials investigated

[en] This work summarizes the experience gained during a long work with wall-less, proportional multiwire counters containing in a single frame the main detector surrounded by a ring of guard counters. The simple and reliable fastening structure of the multiwire system is presented; the technical and operational characteristics of counters made of copper and quartz are given. The intrinsic background of these counters in the energy range of 4 to 20 keV has been studied. Direct measurements of end effects using ₃₇Ar isotope were carried out. (orig.)

No abstract available

[en] We consider the multielemental proportional counter (MEPC) as a detector of weakly interacting galactic-halo candidate particles. We performed calculations of expected counting rate for several gases and their isotopes and estimated the background. We discuss the possibility to set the limit on the WIMP mass ∼ < 1 GeV and to test the composition of the galactic halo

[en] A low-background installation was constructed at the depth of 660 m w.e. where muon intensity is equal to 1 muon per day per cm². The γ-background was decreased by a factor of more than 10³ by special low-radioactive concrete, pure ultrabasic rock and metal shield from steel, lead, copper and tungsten. Around the low-background installation are guard scintillator sheets in anticoincidence connection with the main detector. (author)

[en] Abstract only

[en] The large-volume multiwire pulse ionization chamber for the ions collection was examined as the α-particles detector from the radon decays in the air inside the chamber. The possibility was also studied for obtaining the spectrometric information from the slow ion pulses. The energy resolution of 3.9% for the 5.49 MeV α-particles was obtained in the preliminary measurements. It was shown, that the detector of such type might be applied for direct measurements of the radon activity in the flow-through air at the level lower than 1 Bq/m³. The radon concentration at the level of 10 Bq/m³ may be measured with the accuracy better then 10% for the 10³ s counting time. The detector will be used for the ²²²Rn continuous accurate monitoring in the air of the underground laboratories

[en] The conceptual scheme of an ecologically clean thermal neutron source (TNS) based on muon-catalyzed fusion (MCF) is proposed. The preliminary design shows that an MCF-based TNS can produce the maximum value of unperturbed thermal neutron flux 10¹⁵ n/cm² s using for muon production a beam power of about 14 MW supplied by an accelerator of the next generation. (orig.)