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arXiv · 2610.26121

Experimental verification of the PRIORA Monte Carlo code for proton radiography

Dmitry Varentsov·Martin Schanz·John Schmidt
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Abstract

PRIORA (Proton Radiography Ion-Optical Ray-tracing Analysis) is a fast Monte Carlo model for high-energy proton radiography. It combines fitted proton-matter interaction tables with energy-dependent transfer maps of arbitrary order and simulates approximately $10^6$ protons/s through a complete ion-optical system on an 8-core laptop. We verify it with GSI data obtained with the Ta_bench target: fifteen precision slits in a 2 mm Ta plate between symmetric PMMA staircases. A single experimental image provides the image scale, spatial resolution as a function of chromatic load, signed focus in both planes, effective angular acceptance and multiple-scattering contrast. With identical processing of experiment and simulation and no physics adjustment, PRIORA reproduces the data obtained with 2 and 4 GeV protons. At 2 GeV, PRIORA also recovers sub-percent quadrupole trims consistent with the control-system records and determines a target-plane spatial resolution of $115\pm6\,μ$m.

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Dmitry Varentsov, Martin Schanz, John Schmidt. 2026-10-19. Experimental verification of the PRIORA Monte Carlo code for proton radiography. https://arxiv.org/abs/2610.26121

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