Photospallation of Complex Nuclei at Intermediate Energies. III: Comparison with PICA Calculation

Abstract

Monte Carlo calculations based on the PICA (Photon-Induced Intranuclear Cascade Analysis) code by Gabriel and Alsmiller have been performed for bremsstrahlung-induced spallation of 51 V, 59 Co, 89 Y, 127 1, 133 Cs, 139 La and 197 Au at bremsstrahlung end-point energies of 200 -400 MeV and compared with the experimental results reported in part I of this series of work and others and with the empirical ones reported in part II. The gross features of the experimental and empirical mass and isotopic distributions were found to be reproduced by the PICA code qualitatively for lighter targets of mass = 51-89, but not for heavier targets. The limitations of the reproducibility by the PICA code were examined. The total photoabsorption cross sections are also discussed.

Recoil properties of radionuclides formed in photospallation reactions on complex nuclei at intermediate energies

“…The difference increases with an increase of A t from a factor of about 1.1 for 93 Nb to about 1.7 for 197 Au on average for the (γ,xnyp) products. This trend of the agreement and the disagreement is consistent with the findings from the systematic yield measurements of photospallation by Sarkar et al [4]. The PICA code can reproduce the spallation yields of the medium-mass targets from nat V to 89 Y at E 0 ϭ 400 MeV, but the code gives the yields higher than the observed ones, and results in asymmetric isotopic yield distributions for targets heavier than A t ϭ 100.…”

“…The other details of the calculation, such as the required input parameters, are described in Refs. [15,16] and also in our previous papers [4,48,49]. The E0-independent feature of the observed recoil properties at E 0 Ն 600 MeV indicates that giant resonance, quasi-deuteron mechanism and (3,3) resonance are the main entrance channels for the reactions of interest, and the contributions of multiple pion productions by photons of energies higher than E 0 ϭ 600 MeV are negligible.…”

Recoil properties of radionuclides formed in the photonuclear reactions onnatCu at intermediate energies

“…We have been measuring the yields of bremsstrahlung-induced photopion reactions, 1-4 photospallation, [5][6][7][8] photofragmentation, 9 and/or photofission 10 from 7Li to 2~ targets using radiochemical techniques in order to study the systematics of photonuclear reactions and to investigate reaction mechanisms and nuclear structure. Many fruitful informations about these aspects have been obtained so far, but all based on the yield measurements of reaction products.…”

Photofission of209Bi at intermediate energies

“…In our group, yields of bremsstrahlung-induced reactions such as photopion reactions [1][2][3][4], photospallation [5][6][7][8] and photofragmentation [9,10] on various targets from 7 Li to 209 Bi have been measured by radiochemical techniques to extract information on reaction mechanisms and nuclear structures. These systematic studies are also of importance for practical applications such as astrophysics, medicine, accelerator technology and nuclear waste transmutation.…”