Antonin Vacheret (Imperial College London)
A GMAPD array (sometimes called SiPM) consists of a pixelated array of independent Geiger-Mode avalanche photo-diodes. GMAPD arrays have many potential attractive features, including high photon detection efficiency, high gain (5x10^5,10^6), low timing jitter, insensitiveness to magnetic field, compact design, and low operation voltage. I will present an overview of the newly developed GMAPD arrays and their application in HEP. After a brief history of the birth of the technology I will review in detail the performance of these devices, their advantages and their limitations. In particular, a full evaluation of the Hamamatsu 1.3 mm x1.3 mm active area Multi-Pixels Photon Counters to be used in the Tokai to Kamioka (T2K) neutrino long baseline experiment will be presented. I will then conclude with an short outlook of other potential use of such devices.