Spectral and spatial shaping of laser-driven proton beams using a pulsed high-field magnet beamline

Florian-Emanuel Brack; Florian Kroll; Lennart Gaus; Constantin Bernert; Elke Beyreuther; Thomas E. Cowan; Leonhard Karsch; Stephan Kraft; Leoni A. Kunz-Schughart; Elisabeth Lessmann; Josefine Metzkes-Ng; Lieselotte Obst-Hübl; Jörg Pawelke; Martin Rehwald; Hans-Peter Schlenvoigt; Ulrich Schramm; Manfred Sobiella; Emília Rita Szabó; Tim Ziegler; Karl Zeil

arXiv · 1910.08430

Spectral and spatial shaping of laser-driven proton beams using a pulsed high-field magnet beamline

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Abstract

Intense laser-driven proton pulses, inherently broadband and highly divergent, pose a challenge to established beamline concepts on the path to application-adapted irradiation field formation, particularly for 3D. Here we experimentally show the successful implementation of a highly efficient (50% transmission) and tuneable dual pulsed solenoid setup to generate a homogeneous (8.5% uniformity laterally and in depth) volumetric dose distribution (cylindrical volume of 5 mm diameter and depth) at a single pulse dose of 0.7 Gy via multi-energy slice selection from the broad input spectrum. The experiments have been conducted at the Petawatt beam of the Dresden Laser Acceleration Source Draco and were aided by a predictive simulation model verified by proton transport studies. With the characterised beamline we investigated manipulation and matching of lateral and depth dose profiles to various desired applications and targets. Using a specifically adapted dose profile, we successfully performed first proof-of-concept laser-driven proton irradiation studies of volumetric in-vivo normal tissue (zebrafish embryos) and in-vitro tumour tissue (SAS spheroids) samples.

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Florian-Emanuel Brack, Florian Kroll, Lennart Gaus, Constantin Bernert, Elke Beyreuther, Thomas E. Cowan, Leonhard Karsch, Stephan Kraft, Leoni A. Kunz-Schughart, Elisabeth Lessmann, Josefine Metzkes-Ng, Lieselotte Obst-Hübl, Jörg Pawelke, Martin Rehwald, Hans-Peter Schlenvoigt, Ulrich Schramm, Manfred Sobiella, Emília Rita Szabó, Tim Ziegler, Karl Zeil. 2019-10-18. Spectral and spatial shaping of laser-driven proton beams using a pulsed high-field magnet beamline. https://arxiv.org/abs/1910.08430

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