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FoMos makes double-sided emulsion tapes. Films of desired size cut from such tapes are used as emulsion trackers. The technique for measuring distortions is described, and the results of measurements are presented for several films cut from different sections of a standard piece of double-sided tape with a length of ∼7 m and a useable width of ∼20 cm. The standard plastic base of the tape under investigation is 190 μm thick; ∼50-μm-thick layers of diluted PX3 emulsion–gel are applied to its opposite sides.

It is shown that the use of formulas of paraxial optics in the spatial reconstruction of grain coordinates which are measured by a microscope with a wide-aperture objective lens in an emulsion tracker plate may lead to a systematic error. The error vanishes, if, in these formulas, a single phenomenological parameter aeffwith a value lying between zero and the numerical aperture of the lens. The results of the combined analysis of a series of film thickness measurements for films with various refractive indices nallowed us to estimate aeffparameters for several lenses. With no allowance for correction, the relative systematic error is +0.6% in measurements with a TIYODA 60×/1.0 immersion lens in a plastic layer with npl= 1.49 and –0.2% in measurements in an emulsion with nem= 1.53 with the same objective lens. Measurements with a LOMO 40×/0.65 lens yielded corresponding errors of –3.4 and –3.6%.

The principal characteristics of the modifications of nuclear photomaterials based on the relativistic emulsion P-2 are presented, and test data for various nuclear photoemulsions produced in the last few years are given.

Cryogenically sensitive nuclear emulsion was placed inside the 15-foot bubble chamber of FNAL and exposed to a wide-band energy (up to 200 GeV) neutrino beam. 194 charged-current neutrino interactions and 13 decays of charmed particles were registered. Using the nuclear emulsion as a vertex detector with the good spectrometric properties of the 15-foot bubble chamber has allowed the decays of charmed particles to be effectively analysed. Attentions is focussed on the new physical results. ?c+ baryon andDs+ meson decay channels, production of charmed ?c baryons and ?c+ via ?c. For the first time an event interpreted as production of the excited (c )-state with mass ~2790 MeV/c2 has been registered.

The limits on the parameters of thevμ→vτ oscillations are obtained in the E-564 hybrid experiment: Δm2≦4.5 eV2 and sin2(2θ)≦6.0·10−2 (90% CL). A possibility of direct observation of τ-lepton decays in the nuclear emulsion vertex detector allowed the sensitivity of this experiment to the parameters of the oscillations to be increased.

The WA95/CHORUS experiment at CERN is a dedicated vμ−vτoscillation search experiment. Using the wide band neutrino beam of the CERN-SPS accelerator, with an exposure of 2.4 × 1019protons on the target, this experiment will explore the domain of small mixing angles down to sin22θμτ≈ 3 × 10−4for mass differences Δm2> 1 eV2, more than one order of magnitude better than the current limits. The conceptual design of the CHORUS experiment and data on the detector performances are reported.

Experimental results on the study of quasielastic reactionsvµn?µ-p and $$\bar v_u p \to \mu ^ + n$$ in the energy range 3–30 GeV are presented in this paper. Spark chamber detector with Al filters has been exposed to the wide-band neutrino and antineutrino beams at Serpukhov. Neutrino and antineutrino data have been used to reconstruct the behaviour of axial-vector form-factorFA(Q2). We measured the total cross-sections as a function of energy. The parameterMA=(1.00±0.04) GeV/c2 has been determined under the assumption of the dipole parametrization and CVC hypothesis. Upper limit for the second class currents was estimated.

Backward emitted protons with momentump>0.3 GeV/c in interactions of neutrino in the energy range 10–200 GeV with photoemulsion nuclei were investigated. Energy spectrum slope parameter of backward protons was measured to beT0=48.9±7.9 MeV. TheA-dependence power index of relative mean yield of backward protons was found to bea=0.68±0.12. A drop in the mean yield of backward protons at the four momentum squared over ~15 (GeV/c)2 (the neutrino energy over ~50 GeV) was observed.

The article demonstrates that the mass use of basalt fiber concrete (BFC) is constrained by insufficient study of their durability and serviceability in a variety of environments. This research is aimed at the study of the basalt fiber corrosion processes in the cement stone of BFC, the control of the new products structure formation in order to protect the reinforcing fiber from alkaline destruction and thereby improve the exploitational characteristics of the composite. The research result revealed that the modification of basaltfiber concrete by the dispersion of MWNTs contributes to the directional formation of new products in the cement matrix. The HAM additive in basaltfiberconcrete provides for the binding of portlandite to low-basic calcium hydroaluminosilicates, thus reducing the aggressive effect of the cement environment on the reinforcing fibers properties. The complex modification of BFC with nanostructured additives provides for an increase in its durability and exploitational properties (strength, frost resistance and water resistance) due to basalt fiber protection from alkali corrosion on account of the compacting of the contact zone "basalt fiber - cement stone" and designing of the new products structure and morphology of cement matrix over the fiber surface.