Response of SOI image sensor to therapeutic carbon ion beam

TL;DR

This study evaluates the SOPHIAS SOI image sensor's response to therapeutic carbon ion beams, demonstrating its ability to distinguish particles and observe LET dependence, which is crucial for cancer radiotherapy dose assessment.

Contribution

First assessment of SOPHIAS sensor's performance with therapeutic carbon ion beams, highlighting its particle discrimination and LET dependence detection capabilities.

Findings

Primary and secondary particles are distinguishable by SOPHIAS.

LET dependence observed at high LET regions.

Potential for improved dose measurement in carbon ion therapy.

Abstract

Carbon ion radiotherapy is known as a less invasive cancer treatment. The radiation quality is an important parameter to evaluate the biological effect and the clinical dose from the measured physical dose. The performance of SOPHIAS detector, which is the SOI image sensor having a wide dynamic range and large active area, was tested by using therapeutic carbon ion beam at Gunma University Heavy Ion Medical Center (GHMC). It was shown that the primary carbon and secondary particles can be distinguishable by SOPHIAS detector. On the other hand, a LET dependence was observed especially at the high LET region. This phenomenon will be studied by using the device simulator together with Monte Carlo simulation.