Abstract:
Current state-of-the-art environmental, clinical, and in-vivo radiation sensing systems utilizing various inorganic and tissue-equivalent plastic scintillators are not user
friendly, suffer from electron-beam-generated noise, and are difficult to deploy successfully
for real-time dosimetry. A robust, real-time detection system using different scintillating
materials coupled to solid-state detectors by optical fibers is developed. This system enables radiation monitors/clinicians to conduct meaningful real-time measurements using
different inorganic scintillators or organic, tissue-equivalent plastic scintillators in harsh
clinical and environmental environments.
Recent solid state photomultiplier (SSPM) technology has matured, reaching a performance level that is suitable for replacement of the ubiquitous photomultiplier tube in
selected applications for environmental radiation monitoring, clinical dosimetry, and medical imaging purposes. The objective of this work is laboratory and clinical testing of the
Hamamatsu MPPC (S10362-11-050C), Photonique SSPM (0810G1), and Voxtel SiPM
(SQBF-EKAA/SQBF-EIOA) SSPMs coupled to different inorganic scintillator crystals
(Prelude 420, BGO), inorganic doped glass scintillator material SiO₂: Cu²⁺, and organic
BCF-12 plastic scintillating fibers, used as detector elements. Both polymer optical fibers
(POFs) and glass optical fibers (GOFs) are used as signal conduits for laboratory and
clinical testing. Further, reduction of electron-beam-generated Cerenkov light in optical
fibers is facilitated by the inclusion of metalized air-core capillary tubing between the
BCF-12 plastic scintillating fiber and the POF.
Dose linearity, percent depth dose, and angular measurements for 6 MV/18 MV
photon beams and 9 MeV electron beams are compared using the Hamamatsu MPPC
with-and without the use of the metalized air-core capillary tubing for BCF-12 plastic
scintillating fiber. These same measurements are repeated for SiO₂: Cu²⁺ scintillator
material without air-core capillary tubing.
