title: Comparative Characterization Study of a LaBr3(Ce) Scintillation Crystal in Two Surface Wrapping Scenarios: Absorptive and Reflective.
abstract: The properties of a 50 mm × 50 mm × 30 mm monolithic LaBr3:Ce scintillator crystal coupled to a position-sensitive multi-anode photomultiplier (PMT, Hamamatsu H9500), representing the absorbing detector of a Compton camera under study for online ion (proton) beam range verification in hadron therapy, was evaluated in combination with either absorptive or reflective crystal surface coating. This study covered an assessment of the energy and position-dependent energy resolution, exhibiting a factor of 2.5-3.5 improvement for the reflectively wrapped crystal at 662 keV. The spatial dependency was investigated using a collimated (137)Cs source, showing a steep degradation of the energy resolution at the edges and corners of the absorptively wrapped crystal. Furthermore, the time resolution was determined to be 273 ps (FWHM) and 536 ps (FWHM) with reflective and absorptive coating, respectively, using a (60)Co source. In contrast, the light spread function (LSF) of the light amplitude distribution on the PMT segments improved for the absorptively wrapped detector. Both wrapping modalities showed almost no differences in the energy-dependent photopeak detection efficiency.
authors.affiliation: Faculty of Physics, Ludwig-Maximilians-University Munich , Munich , Germany ; Department of Physics and Astronomy, King Saud University , Riyadh , Saudi Arabia.
authors.forename: Saad
authors.initials: S
authors.lastname: Aldawood
authors.affiliation: Faculty of Physics, Ludwig-Maximilians-University Munich , Munich , Germany ; Faculty of Science, University of Lisbon , Lisbon , Portugal.
authors.forename: Ines
authors.initials: I
authors.lastname: Castelhano
authors.affiliation: Physik Department E12, Technical University Munich , Garching , Germany.
authors.forename: Roman
authors.initials: R
authors.lastname: Gernhäuser
authors.affiliation: Faculty of Physics, Ludwig-Maximilians-University Munich , Munich , Germany ; Faculty of Applied Science, Radiation Science and Technology, Delft University of Technology , Delft , Netherlands.
authors.forename: Hugh
authors.initials: H
authors.lastname: Van Der Kolff
authors.affiliation: Faculty of Physics, Ludwig-Maximilians-University Munich , Munich , Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Lang
authors.affiliation: Faculty of Physics, Ludwig-Maximilians-University Munich , Munich , Germany.
authors.forename: Silvia
authors.initials: S
authors.lastname: Liprandi
authors.affiliation: Faculty of Physics, Ludwig-Maximilians-University Munich , Munich , Germany.
authors.forename: Rudolf
authors.initials: R
authors.lastname: Lutter
authors.affiliation: Physik Department E12, Technical University Munich , Garching , Germany.
authors.forename: Ludwig
authors.initials: L
authors.lastname: Maier
authors.affiliation: Faculty of Physics, Ludwig-Maximilians-University Munich , Munich , Germany.
authors.forename: Tim
authors.initials: T
authors.lastname: Marinšek
authors.affiliation: Faculty of Applied Science, Radiation Science and Technology, Delft University of Technology , Delft , Netherlands.
authors.forename: Dennis R
authors.initials: DR
authors.lastname: Schaart
authors.affiliation: Faculty of Physics, Ludwig-Maximilians-University Munich , Munich , Germany.
authors.forename: Katia
authors.initials: K
authors.lastname: Parodi
authors.affiliation: Faculty of Physics, Ludwig-Maximilians-University Munich , Munich , Germany.
authors.forename: Peter G
authors.initials: PG
authors.lastname: Thirolf
keywords: Compton camera; LaBr3:Ce scintillator; crystal surface coating; medical imaging; γ spectroscopy