Production of isomeric states in the deuteron-induced reaction of gold and lead at high-energies

Abstract

The main objective of the present project is the production and investigation of nuclides in isomeric states.For this purpose the experiments of irradiation of gold and lead targets with high-energy deuterons (3-5 GeV) should be accomplished approximately at the middle of June 2014 (with gold target) and at September 2014 (with lead target) using external beams from the Nuclotron of the Laboratory of High Energy Physics at the Joint Institute for Nuclear Research, Dubna, Russia. The measurements are going to be performed by direct counting $\gamma$-spectra of the irradiated targets with calibrated HpGe spectrometers. Measurements of the cross sections for the reaction products are going to be performed by using the off-line induced-activity method. By this technique we can determine the cross sections and kinematic characteristics of the reaction products. The measured energies of the nuclear $\gamma$-transitions of the different radioactive isotopes in targets and their decay during registration time as well allow to identify the reaction products within the time range between 15 minutes and 1 year, using their nuclear transition energies, intensities, and half-lives. In such way it is possible to measure isotopes which have short half-lives (such as $^{198}$Au$^{m,g}$, $^{85}$Sr$^{m,g}$), as well as long half-lives (as $^{95}$Tc$^{m,g}$, $^{102}$Rh$^{m,g}$, $^{184}$Re$^{m,g}$). Based on the measured independent cross section ratio, the average intrinsic angular momentum of the primary nuclei can be estimated by means of a simple statistical-model analysis based on the formalism developed by Huizenga and Vandenbosch. This project represents the logical continuation of the first BEPE FAPESP 2013/01754-9 approved by FAPESP, with the final report approved by FAPESP, after my return. It was also developed with the same international group, which joins such experienced and respectful researchers in the scientific community from different countries and laboratories as Profs. I. Adam, K Katovsky, O.A.P. Tavares, A. Deppman, A. Balabekyan, F. Garcia, V. Guimar\~aes, V. M. Tsoupko-Sitnikov etc. Our international scientific team was built less than 2 years ago but already achieved very good results and has the aim demonstrate the efficiency of strong collaborative work among common projects and tasks.The present project will give us an opportunity to have access to tools and instruments not available yet in USP laboratories, to strengthen a scientific collaboration already underway with guest team in JINR. It will give the globe contribution to Brazilian science of completely new data in the field of high-energy nuclear reactions and will serve as benchmarks and adoption of existing theoretical models for broad range of energy with different projectiles. (AU)