An upgrade of the long baseline neutrino experiment T2K ND280 near detector is under development with the goal to reduce systematic uncertainties in the prediction of number of events at the ...Super-Kamiokande far detector. The upgrade program includes the design and construction of a new neutrino target, a novel highly granular fully active scintillator detector with 3D WLS fiber readout. The ∼2 tonnes 192 × 192 × 56 cm3 detector will be assembled from 2 × 106 plastic scintillator cubes of 1 × 1 × 1 cm3 size. Each cube is read out by three orthogonal Kuraray Y11 WLS fibers threaded through the detector. A detector prototype made of 125 cubes was assembled and tested in a charged particle beam at CERN in October 2017. This paper presents results from studies of light yield, time resolution and optical cross-talk between the cubes.
A mesoporous silica support was synthesized using the sol-gel method from trichlorosilane. There is a tendency for the specific surface area and the proportion of silica particles mesopores to ...increase during all stages of sol-gel synthesis. It has been shown that the insertion of hexane and toluene, as additional solvents, into the structure-forming polyethylene glycol, makes it possible to regulate the pore size and specific surface area of silica. Silica functionalization was carried out using SILP technology. The activities of the catalytic systems based on polymer and inorganic supports immobilized by imidazole-based ionic liquids during the trichlorosilane disproportionation reaction were compared. There is a tendency for the monosilane yield for catalytic systems based on an inorganic support to increase. We identified the most promising catalyst in terms of monosilane yield and proposed a bifunctional catalyst that exhibited activity in two parallel reactions: trichlorosilane disproportionation and silicon tetrachloride hydrogenation.
The presence of Heavy Neutral Leptons (HNL,
M
≈
O
(1 GeV)), or heavy sterile neutrinos is proposed in various theories in order to solve current problems of the Standard Model (SM), e.g. the origin ...of (tiny) neutrino masses, dark matter, baryon asymmetry etc. The T2K provides intense neutrino beam from both pion and kaon parents and hence allows to carry out experimental search for the HNL of <500 MeV mass range. We have performed the search of the HNL based on the usage of the low-density region in ND280, Time Projection Chambers (TPC) with MC data. This article provides the summary of the MC simulation, event selection, systematics study. We obtain that with the T2K data we can expect the improvements of the limits on the HNL mixing elements for the high mass region (
M
HNL
> 0.44 GeV) and the cross-check of the previous results for lower masses.
Results of sintering cubic boron nitride powders clad with titanium compounds by the high-pressure high-temperature (HPHT) method are presented. Data on the phase composition, microstructure, and ...physical and mechanical properties of the resulting composite materials are presented.
Synthesis of inorganic polysilazane by ammonolysis of dichlorosilane in pyridine was investigated. With increasing the flow of ammonia into the reactor, the polysilazane molar weight decreases, and ...the polymer molecule structure becomes more linear. A decrease in the flow leads not only to a rise in the molar weight of the product, but also to the appearance of branched segments of the polymer chain. The minimum required amount of pyridine, providing a high yield of the product was 2.6 mol per 1 mol of dichlorosilane. A decrease in the synthesis temperature results in an increase in the product yield.
An upgrade of the Near Detector of the T2K long baseline neutrino oscillation experiment, ND280, has been proposed. This upgrade will include two new Time Projection Chambers, each equipped with 16 ...resistive Micromegas modules for gas amplification. A first prototype of resistive Micromegas has been designed, built, installed in the HARP field cage, and exposed to a beam of charged particles at CERN. The data have been used to characterize the performances of the resistive Micromegas module. A spatial resolution of 300 μm and a deposited energy resolution of 9% were observed for horizontal electrons crossing the TPCs at 30 cm from the anode. Such performances fully satisfy the requirements for the upgrade of the ND280 TPC.
Selection is substantiated for an iodine-transport method for vapor phase deposition of a Ti-compound layer with uniform thickness over the surface of cubic boron nitride powder grains used as a ...precursor for subsequent formation of a nitride-boride binder phase for a final composite material. This is a promising material for thermally stable, high-hardness, cutting tools, resistant to impact and corrosion. The process of plating cubic boron nitride (
c
BN) powder with titanium compounds through a vapor phase transport method is studied experimentally. Results are provided for microstructure imaging and XPA analysis of the phase composition of the powders obtained.
Experimental studies of changes in the pore structure and physicotechnical properties of carbonized spinel-corundum refractories under different decarbonization conditions and formation of a ...protective control layer on their hot surface suppressing refractory material decarbonization and mass transfer between a lining and molten slag flow are presented. Results of industrial tests of carbonized spinel-corundum refractories in the working layer of a 400-ton steel-ladle, lining as well as topography and refractory specific consumption coefficients for ladle lining functional zones, and the amount of refractory lining breakdown products during operation are considered.
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