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The first experiments were carried out to study the elemental composition of archaeological ceramics using prompt gamma activation analysis (PGAA) at the pulsed reactor IBR-2, Frank Laboratory of Neutron Physics (FLNP) - Joint Institute for Nuclear Research (JINR). A radiation-resistant n-type High Purity Germanium (HPGe) detector was used to measure the radioactivity. The concentrations of 14 elements were determined namely; Al, C, Ca, Fe, Gd, H, K, Mn, Na, P, S, Si, Sm, and Ti. The obtained results were compared with those analyzed by other analytical techniques INAA (Instrumental Neutron Activation Analysis) and portable X-ray fluorescence (XRF) for the same archaeological batches. The results revealed a good agreement within a range of 1-30%. These insights will contribute to the discussion of improving the PGAA installation and automation of the data obtained, which in turn will improve the quality of analysis and increase the number of determined elements. In this work results are presented, and the analytical merits are compared.

New results of the neutron-proton spin-dependent total cross section difference $\Delta\sigma_L(np)$ at the neutron beam kinetic energies 1.59, 1.79 and 2.20 GeV are presented. Measurements were performed at the Synchrophasotron of the Laboratory of High Energies of the Joint Institute for Nuclear Research in Dubna. A quasi-monochromatic neutron beam was produced by break-up of extracted polarized deuterons. Neutrons were transmitted through a large polarized proton target. Measurements were performed either with a parallel or an antiparallel beam and target polarizations, both oriented along the beam momentum. The results at the two higher energies were measured with two opposite beam and target polarization directions. Only one target polarization direction was available at 1.59 GeV. The present measurements agree well with existing data. A fast decrease of the $-\Delta\sigma_L(np)$ values with increasing energy above 1.1 GeV was confirmed. The new results are also compared with model predictions and with phase shift analysis fits. The $\Delta\sigma_L$ quantities for isosinglet state I=0, deduced from the measured $\Delta\sigma_L(np)$ values and known $\Delta\sigma_L(pp)$ data, are given.

The polarization left‐right asymmetry and angular fore‐aft asymmetry of γ yields were investigated for the direct transition Eγ=9.04 MeV in 114Cd near the p‐wave resonance Ep=7 eV. The experiments were performed at the pulsed reactor IBR‐30 using an LMN‐polarizer of neutrons and NaJ (T1)‐detectors.

Experiments on the spin dependence of the interaction of resonance neutrons (up to 100 keV) with the rare earth nuclei 141 Pr, 159 Tb, 165 Ho, 167 Er and 169 Tm are reported. The measurements were performed with polarized neutrons and nuclei. The spin dependence of S-wave strength functions was investigated, and the imaginary part of the spin-spin potential ( W ss = 0.10 ± 0.06 MeV) was estimated in optical-model calculations with a potential in the form of a rectangular well. The energy dependence of the difference of strength functions for two J -states shows possible intermediate states in the formation of the compound nucleus. The J -values of about 230 resonances were determined.

Experiments to observe the parity nonconserving effects in 81Br, 111Cd, 117Sn, 127I, 139La and 238U are described. The measurements were performed with a beam of polarized neutrons from the pulsed reactor IBR-30 at Dubna. A dependence of total cross sections on neutron helicity was discovered in the following resonances: 0.88 eV 81Br, 4.53 eV 111Cd, 1.33 eV 117Sn, and 0.75 eV 139La. The effect has a resonance character and is in agreement with theoretical predictions made in the framework of the model of mixing compound states. The paper contains experimental estimates for the mixing coefficients and matrix elements.

The analyzing power and the fore-aft asymmetry were studied in the 117Sn(n,γ) reaction near the 1.33 eV p-wave resonance, where the parity violated. The experiments were performed at the IBR-30 pulsed reactor with the NaI(T1) spectrometer. The neutron width amplitudes and were determined

The 6Li(n,n) cross section value and its dependence on neutron energy in the 0.6–80 keV region are measured at the IBR-30 pulsed reactor by the time-of-flight method. A constant value of 0.72±0.02 barn was found for the scattering cross section below 10 keV. The energy dependence of the 6Li(n,n) cross section together with other data were analysed in the frame of R-matrix formalism to clarify the properties of levels of the 7Li nucleus.

The results on parity-nonconserving (PNC) effects in p-wave neutron resonances are reported. The experiments were carried out at the IBR-30 pulsed reactor with the neutron beam polarized by trans-mission through a polarized proton target. The dependence of total cross section on longitudinal polarization vi/as found for the resonances at 0.88 eV 81Br, 5.53 eV 111Cd, 1.33 eV 117Sn and 0.75 eV 139La. The PNC effect has the resonance shape. These results were analysed together with thermal neutron data in the frame of the model of compound states mixed due to weak nucleon interaction.