TAILIEUCHUNG - The study of isomeric ratios in photonuclear reactions forming high spin isomers in the giant dipole resonance region
The results were analyzed, discussed and compared with those of other authors as well as with theoretical model calculations. The study shows that the isomeric ratios in nuclei with high spin isomeric states are much lower than that in low spin isomeric state isomers. | Communications in Physics, Vol. 24, No. 4 (2014), pp. 381-389 DOI: THE STUDY OF ISOMERIC RATIOS IN PHOTONUCLEAR REACTIONS FORMING HIGH SPIN ISOMERS IN THE GIANT DIPOLE RESONANCE REGION TRAN DUC THIEP, TRUONG THI AN, PHAN VIET CUONG, NGUYEN THE VINH, AND BUI MINH HUE Institute of Physics, VAST, 10 Dao Tan St., Ba Dinh Region, Hanoi, Vietnam A. G. BELOV AND O. D. MASLOV Flerov Laboratory of Nuclear Reactions, JINR, 141980 Dubna, Moscow Region, Russia E-mail: tdthiep@ Received 26 November 2014 Accepted for publication 12 December 2014 Abstract. We studied the isomeric ratios in odd-odd nuclei 196 Au, 182 Ta and 194 Ir with high spin isomeric states produced in 197 Au(γ, n)196m,g Au, 183 W(γ, p)182m,g Ta and 185 Pt(γ, p)194m,g Ir reactions by using the activation technique and γ-ray spectroscopic method in the giant dipole resonance (GDR) region. The high-purity natural Au, W and Pt foils in disc shape were irradiated with bremsstrahlungs generated from an electron accelerator Microtron. The irradiated foils were measured by the high resolution γ-ray spectroscopic system which consists of a Ge(HP) detector and a multichannel analyzer. In order to improve the accuracy of the experimental results, necessary corrections were made in the γ-ray activity measurements and data analysis. The results were analyzed, discussed and compared with those of other authors as well as with theoretical model calculations. The study shows that the isomeric ratios in nuclei with high spin isomeric states are much lower than that in low spin isomeric state isomers. Keywords: photonuclear reaction, isomeric ratio, GDR region, reaction yield – impulse. I. INTRODUCTION The isomeric ratios furnish valuable information about the energy level structure of nuclei and the nuclear reaction mechanism involved [1–5]. This quantity depends on the spin of target nucleus and the intake angular momentum determined by the mass and the energy of .
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