Photonuclear Disintegration at High Energies (<350 MeV)

Abstract

Calculations of high-energy (40<£ Y <350 MeV) photon-nucleus (A>\2) collisions have been carried out. The results of the initial interaction of the photon with the nucleus are obtained either from Levinger's quasideuteron model or, when energetically possible, from one of the four-pion-nucleon states formed in photon-nucleon interactions. The effect of nucleon-(pion-) nucleus interactions that follow the initial photon interaction is taken into account by using an intranuclear-cascade model. The results of the calculations are compared with a variety of experimental data, and good agreement is obtained.

Angular distributions of protons from bremsstrahlung of maximum energy 400 MeV incident on elements between lithium and gold

“…Before drawing any definite conclusions as to the nature of the primary process, it is necessary to determine the total corrections given by all the secondary effects. We will, when discussing results obtained with the Gabriel-Alsmiller model [18] in the final paper of this series, show that the discrepancy between the experimental results and those suggested by the above crude picture of intranuclear absorption can be considerably minimized. Calculations with the Gabriel-Alsmiller model reduce the relative magnitude of the discrepancy from about a factor of three (971/3/71/3) to about a factor of 1.5.…”

“…The ideas of Levinger have been further discussed by a number of authors [19][20][21][22][23][24] and, in addition, two attempts [18,[25][26][27] to fit the available experimental data on high-energy photo-nucleon emission starting from experimentally-determined values of the cross-section for deuteron photodisintegration have recently been made. Matthews [25,26] has developed a more complete formulation of Levinger's ideas which has been successfully applied to photo-proton data from light nuclei for photon energies up to 100 MeV.…”

Dose Measurements of Bremsstrahlung-Produced Neutrons at the Advanced Photon Source

“…As discussed earlier, these are t o be calculated from appropriate nuclear models. The photonuclear interaction Monte Carlo PICA (Photon-Induced Intranuclear Cascade Analysis) [22] calculates the results of nuclear reactions caused by the collision of medium energy photons (30 < ET < 1000 MeV) with the nuclei [17]. PICA also calculates results of giant resonance dipole interactions using available cross sections [20,211.…”

Photoproduction of high-energy neutrons in thick targets by electrons in the energy range 150 to 270 MeV

“…These nucleon impulse values correspond to energies of 10.4 and 13.6MeV, respectively. For comparison: Alsmiller and Gabriel [33] assumed for the calculation of the photo-nucleon spectra from light and heavy nuclei a Gaussian distribution for the nucleons inside the nucleus with a 1/e-value of 15 MeV (~168 MeV/c). Recent experimental investigations [7,13,34] on 12C and 160 yield values for between 100 and 120 MeV/c whilst in earlier publications [35][36][37], a-values between 168 and 194 MeV/c have been used, even for such light nuclei as beryllium, carbon and oxygen.…”