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Tagged neutrons are used to perform an experimental investigation of the inelastic scattering of 14.1 MeV neutrons on 23Na and 35Cl nuclei as part of the TANGRA project at the Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research. The energies and yields of γ quanta for transitions observed in the experiment are measured, and the γ angular distribution coefficients for the highest intensity γ transitions are obtained. The experimental data are compared to others in the literature.

The inelastic scattering of 14.1 MeV neutrons off magnesium nuclei is studied at the TANGRA facility using tagged neutrons and an ING-27 standard neutron generator. The energies and partial cross sections of visible γ transitions induced in different reactions between neutrons and magnesium nuclei are determined. The measured angular distribution of γ quanta for 24Mg is analyzed and compared to results from other experimental studies.

The work is devoted to measuring the angular distribution of 4.43-MeV γ-rays produced in inelastic scattering of 14.1-MeV neutrons by 12C nuclei. A portable ING-27 neutron generator (designed and fabricated at VNIIA, Moscow) with a built-in 64-pixel silicon α-detector was used as a source of tagged neutrons. The γ-rays of characteristic nuclear radiation from 12C were detected with a spectrometric system that consisted of 22 γ-detectors based on NaI(Tl) crystals arranged around the carbon target. The measured angular distribution of 4.43-MeV γ-rays is analyzed and compared with the results of other published experimental works.

For investigation of the basic characteristics of 14.1 MeV neutron induced nuclear reactions on a number of important isotopes for nuclear science and engineering, a new experimental setup TANGRA has been constructed at the Frank Laboratory of Neutron Physics of the Joint Institute for Nuclear Research in Dubna. For testing its performance, the angular distribution of γ-rays (and neutrons) from the inelastic scattering of 14.1 MeV neutrons on high-purity carbon was measured and the angular anisotropy of γ-rays from the reaction 12 C(n, n′ γ)12 C was determined. This reaction is important from fundamental (differential cross-sections) and practical (non-destructive elemental analysis of materials containing carbon) point of view. The preliminary results for the anisotropy of the γ-ray emission from the inelastic scattering of 14.1- MeV neutrons on carbon are compared with already published literature data. A detailed data analysis for determining the correlations between inelastic scattered neutron and γ-ray emission will be published elsewhere.

The characteristics of the setup for analyzing the elemental composition of organic substances using spectroscopy of γ rays induced by tagged neutrons with an energy of ∼14 MeV in an inelastic neutron scattering reaction are discussed. An ING-27 D-T neutron generator with a built-in position-sensitive α detector, fast neutron and γ detectors, and a multichannel detecting system providing a subnanosecond time resolution are parts of the experimental setup. The correlation between the exit angle of a neutron and the number of the α pixel, as well as the anisotropy in emission of γ rays in the inelastic neutron scattering reaction, are measured, and the errors of these measurements are estimated.

A neutron generator developed for instrumentation for pulsed neutron logging of oil and gas wells is described in the paper. The generator consists of a power supply, a switching unit, and acceleration tubes placed coaxially on a common chassis in a 42 mm diameter housing. Laboratory and field testing of the generator is very briefly summarized. The small diameter, high neutron flux per pulse, and operating life make the generator suitable for use in experimental neutron physics, investigating nuclear reactors, thermonuclear installation neutron field monitoring, and neutron-activation analysis of elemental material composition. 4 refs., 4 figs.