Researchers develop a proton detector that can directly detect 5-MeV protons by organic thin-film devices.
Development of detectors for protons and other heavy materials has been a research focus for a very long time now. Proton detectors find their applications in monitoring energy and flow of particles in ion beams. Most sophisticated ion beam flow detectors use lasers for reliable monitoring, but more accurate measurement techniques are increasingly needed for various biomedical applications.
High-precision proton detectors are becoming more desirable for proton therapy, in which protons rather than traditional X-rays are fired at cancerous tumors because they can be directed more precisely. The effectiveness of treatment in human tissues is enhanced by tuning the beam both in intensity and in position to irradiate the tumor in a controlled way. For this, accurate recording and mapping of the dose delivered during a treatment plan is needed.
A team of researchers from several institutions in Italy and one in the U.S. has developed an organic thin-film device that can be used to measure doses of proton radiation. The developed detector can directly detect 5-MeV protons by flexible organic detectors based on thin films. Their paper has been published in the journal Science Advances.
The organic device acts as a solid-state detector, in which the energy released by the protons within the active layer of the sensor is converted into an electrical current. These sensors can quantitatively and reliably measure the dose of protons impinging on the sensor both in real time and in integration mode.
According to the researchers, the measured sensitivity, S = (5.15 ± 0.13) pC Gy−1, and limit of detection, LOD = (30 ± 6) cGy s−1, of the here proposed detectors assess their efficacy and their potential as proton dosimeters in several fields of application, such as in medical proton therapy.