A high sensitivity Cherenkov detector for prompt gamma timing and time imaging

Area of Science:

• Medical Physics
• Particle Therapy
• Radiation Detection

Background:

• Real-time monitoring of particle therapy is essential for ensuring treatment accuracy.
• Current methods may have limitations in sensitivity, especially at low particle statistics.
• Prompt Gamma (PG) timing offers a promising avenue for in-situ range verification.

Purpose of the Study:

• To experimentally validate the feasibility of Prompt Gamma Time Imaging (PGTI) in the Single Proton Regime (SPR).
• To develop and characterize a novel Cherenkov-based detector array (TIARA) for PG detection.
• To achieve high sensitivity in proton range measurement for particle therapy monitoring.

Main Methods:

• Development of a multi-channel, Cherenkov-based PG detector (TIARA) with a target time resolution of 235 ps (FWHM).
• Utilized PbF[Formula: see text] crystals and silicon photomultipliers for PG detection and timing.
• Coincidence measurements with a diamond-based beam monitor to record proton time-of-flight.
• Testing prototypes with 63 MeV and 148 MeV protons from different accelerators.

Main Results:

• A first TIARA prototype achieved a time resolution of 276 ps (FWHM) with 63 MeV protons, yielding a 4 mm proton range sensitivity with 600 PGs.
• A second prototype with 148 MeV protons demonstrated a time resolution below 167 ps (FWHM) for the gamma detector.
• Uniform sensitivity across PG profiles was shown to be achievable with uniformly distributed detectors.

Conclusions:

• The developed TIARA detector provides experimental proof-of-concept for high-sensitivity monitoring in particle therapy.
• The system has the potential for real-time feedback during irradiation to ensure compliance with treatment plans.
• This technology can significantly enhance the safety and efficacy of particle therapy treatments.