Spectroscopic study of prompt-gamma emission for range verification in proton therapy

Laurent Kelleter; Aleksandra Wrońska; Judith Besuglow; Adam Konefał; Karim Laihem; Johannes Leidner; Andrzej Magiera; Katia Parodi; Katarzyna Rusiecka; Achim Stahl; Thomas Tessonnier

doi:10.1016/j.ejmp.2017.01.003

Spectroscopic study of prompt-gamma emission for range verification in proton therapy

Phys Med. 2017 Feb:34:7-17. doi: 10.1016/j.ejmp.2017.01.003. Epub 2017 Jan 26.

Authors

Affiliations

¹ Physics Institute 3B, RWTH Aachen University, Aachen, Germany. Electronic address: laurent.kelleter@physik.rwth-aachen.de.
² Marian Smoluchowski Institute of Physics, Jagiellonian University, Kraków, Poland. Electronic address: aleksandra.wronska@uj.edu.pl.
³ Physics Institute 3B, RWTH Aachen University, Aachen, Germany.
⁴ Department of Nuclear Physics and its Applications, Institute of Physics, University of Silesia, Katowice, Poland.
⁵ Marian Smoluchowski Institute of Physics, Jagiellonian University, Kraków, Poland.
⁶ Heidelberg Ion-Beam Therapy Center, Heidelberg, Germany; Department of Medical Physics, Ludwig-Maximilians-Universität München, Munich, Germany.
⁷ Department of Medical Physics, Ludwig-Maximilians-Universität München, Munich, Germany; Department of Radiation Oncology, Heidelberg University Clinic, Heidelberg, Germany.

PMID: 28131731
DOI: 10.1016/j.ejmp.2017.01.003

Abstract

We present the results of an investigation of the prompt-gamma emission from an interaction of a proton beam with phantom materials. Measurements were conducted with a novel setup allowing the precise selection of the investigated depth in the phantom, featuring three different materials composed of carbon, oxygen and hydrogen. We studied two beam energies of 70.54 and 130.87MeV and two detection angles: 90° and 120°. The results are presented in form of profiles of the prompt-gamma yield as a function of depth. In the analysis we focused on the transitions with the largest cross sections: ¹²C_4.44→g.s. and ¹⁶O_6.13→g.s.. We compare the profiles obtained under various irradiation conditions, with emphasis on the shape of the distal fall-off. The results are also compared to calculations including different cross-section models. They are in agreement with the model exploiting published cross-section data, but the comparison with the Talys model shows discrepancies.

Keywords: Prompt-gamma imaging; Proton therapy; Range verification.

MeSH terms

Gamma Rays / therapeutic use*
Phantoms, Imaging
Proton Therapy / instrumentation
Proton Therapy / methods*
Spectrum Analysis