Development of a new type of hybrid photo-detector involving photocathode, scintillator, and silicon photomultiplier

We proposed a new type of hybrid photo-detector that consists of a photocathode, an electrode, a scintillator, and a silicon photomultiplier in a vacuum tube. This type of photo-detector with a large area of photocathode could be utilized in photo-detector array for neutrino detection. Photons incident onto the photocathode are converted to photo-electrons. Due to the electric field between photocathode and electrode, the photo-electrons accelerates toward the scintillator to produce scintillation lights. The scintillation lights, then, enters the silicon photomultiplier SiPM to be converted to an electrical signal. The advantage of this type of photon-detector is that the scintillation lights contributes an extra gain in the order of tens to the total gain in addition to the built-in multiplication gain of at least 106 given from the silicon photomultiplier. We present the test result obtained with a demonstrator built for the principle proof of this new type of photo-detector. We also present the result of electrical field simulation and transit time calculation for this new type of photo-detector.