Experimental results on cross section for 7Be photo-production on 12C, 14N and 16O nuclei

International Conference on Nuclear Chemistry

December 08-09, 2016 San Antonio, USA

V S Malyshevsky

Southern Federal University, Russia

Posters & Accepted Abstracts: J Nucl Med Radiat Ther

Abstract :

At present, the monitoring of radionuclides content in the air-ground interface suggests the conclusion that the radioactivity of ground air is essentially contributed by a short-lived isotope 7Be of cosmic origin. The 7Be isotope presents interest not only from the standpoint of its radioactive effect on biological systems, but also because it can serve as an indicator of the buildup of air-supplied pollutants by natural environments. The last-mentioned property may be conveniently used for estimating a possible atmospheric pollution and air ex-change in the environment. Therefore, the investigation into the mechanisms and regularities of the processes of 7Be generation, transport and migration in the ecosphere objects and at their interfaces appears rather urgent. It is considered that the main reactions leading to beryllium isotope generation in the terrestrial atmosphere take place at interaction of cosmic rays with nitrogen and oxygen nuclei, which are the principal constituents of the atmospheric air. Another possible mechanism of 7Be generation in the upper atmosphere may lie in photonuclear reactions. The results that we obtained amount to the following. The yields of the A(�?³,X)7Be reactions on 12C, 14N, and 16Onuclei have been measured in the energy range of 40â�?�?90 MeV. The cross sections for the A(�?³,X)7Ð�?е reactions on 12С, 14N, and 16O nuclei have been calculated by using the measured yields and the calculated bremsstrahlung spectrum. The experimental cross sections for photonuclear reactions leading to 7Ð�?е production have been compared with their counterparts obtained with the aid of the TALYS 1.4 package. The cross sections for the photo-production of the isotope 7Ð�?е on 14Nand 16O nuclei have been obtained for the first time. Agreement between the results of the measurements and calculations for 12С and 14N nuclei at energies above 50 MeV has been proven.

Biography :

Email: vsmalyshevsky@sfedu.ru