Shielding experiments by the JASMIN collaboration at Fermilab (II) - Radioactivity measurement induced by secondary particles from the anti-proton production target

TL;DR

This study measures nuclear reaction rates induced by secondary particles near the anti-proton production target at Fermilab, comparing experimental data with Monte Carlo simulations to understand particle emission and activation.

Contribution

It provides detailed measurements of reaction rates and their angular dependence, and compares these with Monte Carlo calculations, enhancing understanding of secondary particle production.

Findings

Reaction rates increase at forward angles.

Angular dependence grows with higher energy thresholds.

Monte Carlo results agree within a factor of 2 to 3.

Abstract

The JASMIN Collaboration has performed an experiment to conduct measurements of nuclear reaction rates around the anti-proton production (Pbar) target at the Fermi National Accelerator Laboratory (FNAL). At the Pbar target station, the target, consisting an Inconel 600 cylinder, was irradiated by a 120 GeV/c proton beam from the FNAL Main Injector. The beam intensity was 3.6 x 10**12 protons per second. Samples of Al, Nb, Cu, and Au were placed near the target to investigate the spatial and energy distribution of secondary particles emitted from it. After irradiation, the induced activities of the samples were measured by studying their gamma ray spectra using HPGe detectors. The production rates of 30 nuclides induced in Al, Nb, Cu, Au samples were obtained. These rates increase for samples placed in a forward (small angle) position relative to the target. The angular dependence of these reaction rates becomes larger for increasing threshold energy. These experimental results are compared with Monte Carlo calculations. The calculated results generally agree with the experimental results to within a factor of 2 to 3.