Neutron Physics Department

(Head – Ph. D. O. O. Gritzay)

The department was established in 1973. The Dr. Sci., Professor V. P. Vertebny was the first Head; from 1987 till 1998 the department was headed by Dr. Sci. A. V. Murzin.

Main directions of scientific activity: 

Investigations of nuclear-physics characteristics of nuclei on Kyiv Research Reactor WWR-M:

• Definition of neutron cross sections with high accuracy in interactions of quasi-mono-energy neutrons with average energies from the thermal ones up to ~ 300 кеV for obtaining nuclear-physical characteristics, required for the development of model representations about mechanisms of interaction between neutrons and nuclei.
• Measurements of reaction cross sections with the output of charged particles for studying emission processes of the charged particles.
• Research of gamma spectra from reaction of the radioactive capture averaged over the neutron resonances for obtaining information on spin and parity of the excited states of nuclei.
• Improvement of existing and introduction of new experimental techniques, development and implementation of new neutron filters (including Boron Neutron Capture Therapy tasks).

            The Ukrainian Nuclear Data Center activity and its development

(http: //ukrndc.kіnr.kіev.ua/):

·        compilation of experimental nuclear data given by Ukrainian scientists to the International bases CSІSRS and CІNDA;

·        accumulation and updating information base for carrying out  the nuclear-physical calculations;

·        dissemination of computer codes for fundamental and applied calculations. 

The most important scientific results: 

• Cross-sections of neutron reaction interactions (thermal, resonant and intermediate energies) for more than 100 nuclei were obtained. The majority of the neutron data for the stable and radioactive nuclei were obtained for the first time.
• For the first time the neutron resonances for a group of nuclei were investigated in the area of mass numbers А = 130 - 200. The isotope dependence of the level density of the excited nuclei was established; nuclei with neutron numbers 100 – 110 are shown to have the properties of magic nuclei, thus, Strutinsky theory about the displacement of the closed shells at the deformation of nuclei was experimentally confirmed.
• Large volume of spectroscopic information on properties of the lower excited states of nuclei was obtained. Regularities of disintegration for s-, p- and d-resonances, and dependence of radioactive strength functions on the energy are investigated. Broad set of middle and heavy nuclei was investigated for the establishment of statistical and non-statistical regularities at highly-excited level disintegrations.
• There was the versatile experimental base for investigations of neutron interactions with nuclei using methods of neutron spectrometry, including: time of flight spectrometers for neutron energies from 0.01 up to 10 000 еV; installation for research of  radioactive nuclei; the set of neutron filters on the basis of natural  elements such as Al, Sі, S, Sc, V, Mn, Fe and the enriched isotopes  ⁵²Cr, ^54,56,57 Fe, ^58,60 Ni for formation of 20 quasi-mono-energy reactor neutron beams with average energies from 0.017 eV up to 275 keV; the nuclear reaction chamber for research of a high-energy part of  neutron spectrum in reactor (E_n > 15 MeV), etc. were developed, created and successfully used on the WWR-M Research Reactor.
• Modern system for nuclear data preparation both for scientific research, and for nuclear technologies applications, introduced in Ukraine, has been created and is in operation now.