High-energy threshold reaction rates on 0.8 GeV proton-irradiated thick Pb-target

TL;DR

This study measures threshold reaction rates in various materials exposed to an 800-MeV proton beam on a thick lead target, comparing experimental gamma-spectrometry results with MCNPX simulations to validate nuclear reaction models.

Contribution

It provides comprehensive experimental data on reaction rates in multiple materials and validates simulation codes against these measurements for high-energy proton interactions.

Findings

Good agreement between measured and simulated reaction rates.

Extensive gamma-spectrometry data collected (1196 spectra).

Validated MCNPX code with nuclear data libraries for high-energy reactions.

Abstract

This works presents results of activation-aided determination of threshold reaction rates in 92 209Bi, natPb, 197Au, 181Ta, 169Tm, natIn, 93Nb, 64Zn, 65Cu, 63Cu, 59Co, 19F, and 12C samples and in 121 27Al samples. All the samples were aligned with the proton beam axis inside and outside the demountable 92-cm thick Pb target of 15-cm diameter assembled of 23 4-cm thick discs. The samples were placed on 12 target disks to reproduce the long axis distribution of protons and neutrons. In June 2006, the target was exposed for 18 hours to a 800-MeV proton beam extracted from the ITEP U-10 accelerator. The proton fluence and the proton beam shape were determined using the 27Al(p,x)7Be monitor reaction. The reaction rates were determined by the direct gamma-spectrometry techniques. In total, 1196 gamma-spectra have been measured, and about 1500 reaction rates determined. The measured reaction rates were simulated by the MCNPX code using the following databases: ENDF/B6 for neutrons below 20 MeV, MENDL2 for 20-100 MeV neutrons, and MENDL2P for proton cross sections up to 200 MeV. An acceptable agreement of simulations with experimental data has been found.