[14p-E204-1~21] 2.1 Radiation physics and Detector fundamentals

[14p-E204-9] Luminescence of water during radiation irradiation lower energy than Cerenkov-light threshold

〇Seiichi Yamamoto¹, Toshiyuki Toshito², Takashi Akagi³, Tomohiro Yamashita³, Shuji Koyama¹, Masataka Komori¹ (1.Nagoya Univ, 2.NPTC, 3.HIBMC)

Keywords:radiations, luminescence, Cerenkov-light

We discovered luminescence of water during radiation irradiation to water lower than the Cerenkov-light threshold. It is commonly thought that, no visible light is thought to be produced in water during irradiation of protons below Cerenkov-light threshold. Contrary to this consensus, we found that luminescence was emitted from water with proton irradiation below the threshold. We placed water phantoms set on a table, and luminescence images of water phantom were measured with a high-sensitivity cooled charge coupled device (CCD) camera during 100MeV proton-beam irradiation. The luminescence images of water phantoms showed clear Bragg peak, and the measured proton ranges from the images were almost the same as those obtained with an ionization chamber. We also tried the imaging of water for carbon-ion, alpha particles and low energy X-ray photons lower energy than Cerenkov-light threshold and the luminescence of water was observed and imaging was possible for all these radiations. We will also show the light output and spectra for the luminescence of water in the meeting.