Excitation function of the 181 Ta(α*n)184 Re reaction

• Autor(a) principal: Santos, Wilma Machado Soares
• Data de Publicação: 1994
• Outros Autores: Barros, S. de (?), Suita, Julio Cezar, Auler, Luiz Telmo, Peterson, Jerry, Instituto de Engenharia Nuclear, University of Colorado
• Tipo de documento: Artigo de conferência
• Idioma: eng
• Título da fonte: Repositório Institucional do IEN
• Texto Completo: http://carpedien.ien.gov.br:8080/handle/ien/2706
• topic: RTFNB 1994; Excitation function; Residual activity

Excitation function of the 181 Ta (a,n) 184 Re reaction in the energy range from 14 to 28 MeV was measured by the residual activity induced in metal tantalum foils 99,9% purity and nominal thicknesses of 5 and 10 pm), by a beams produced in the I.E.N. Cyclotron. The cross sections were obtained in four differents irradiation sets, and are very consistents among them. They were measured using both 7-rays peaks of 792 and 903 keV from 194 Re decay. The errors associated with these values were obtained from error propagation formula including those due to foil energy uncertainty (4%), to target foil thickness (4%), to the detector efficiency (5%), to charge collection (10%), and to statistical errors in the-peak area of our 7 spectra. The total error is about of 15%. The present results were compared with those obtained by Scott') and by Ismail 21 . The amount of experimental data in this work is greater than the obtained by Scott et al., who presents total error bars of about 20%. Our results are about 30% lower than the Scott's one, but the shape of the curves are similar and differs from the . Ismail's curve shape. The comparison of our experimental results with the theoretical calculations 3) performed with the STAPRE code 4 ) (Hauser-Feshbach model with pre-equilibrium emission), shows that calculations with pre-equilibrium reproduces quite well the shape of the excitation curve in this energy interval.