Soft proton experiments supporting the development of astronomical X-ray instrumentation

S. J. Diebold; B. Heß; F. Pfeifle; L. Ph. H. Schmidt; C. Tenzer; T. Wildfang; D. Ferreira; M. Freyberg; S. Massahi; D. Paredes-Sanz; E. Perinati; A. Santangelo; B. Stelzer; S. Svendsen

doi:10.1117/12.3105400

arXiv · 2608.29743

Soft proton experiments supporting the development of astronomical X-ray instrumentation

S. J. Diebold·B. Heß·F. Pfeifle·L. Ph. H. Schmidt·C. Tenzer·T. Wildfang·D. Ferreira·M. Freyberg·S. Massahi·D. Paredes-Sanz·E. Perinati·A. Santangelo·B. Stelzer·S. Svendsen

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Abstract

Orbital soft protons can severely degrade the performance of astronomical X-ray observatories. On the one hand, they may cause permanent radiation damage to X-ray detectors; on the other hand, they introduce an irreducible background component. Our low-energy grazing-incidence scattering setup provides experimental data for the validation of radiation transport simulations used in the assessment of future X-ray missions. Recent measurements indicate that a significant fraction of protons scattered from X-ray optics undergo charge exchange and therefore cannot be mitigated by magnetic diverters. In addition, we present initial proton-transmission measurements through a thin X-ray filter and compare them qualitatively with TRIM simulations. Quantitative measurements of energy loss and charge-exchange fractions, together with comparisons with TRIM and Geant4, are planned. In this publication, we present the upgraded experimental setup together with commissioning measurements for grazing-incidence scattering and proton transmission through thin X-ray filters.

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S. J. Diebold, B. Heß, F. Pfeifle, L. Ph. H. Schmidt, C. Tenzer, T. Wildfang, D. Ferreira, M. Freyberg, S. Massahi, D. Paredes-Sanz, E. Perinati, A. Santangelo, B. Stelzer, S. Svendsen. 2026-08-30. Soft proton experiments supporting the development of astronomical X-ray instrumentation. https://doi.org/10.1117/12.3105400

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