Performance Studies of the New Generation Amperex Xp2020 Photomultiplier

Characteristics have been measured for the new generation Amperex XP2020 45 mm-diameter photomultiplier. Some typical photomultiplier characteristics--such as gain, dark current, transit and rise times--are compared with data provided by the manufacturer. Photomultiplier characteristics generally not available from the manufacturer, such as the single photoelectron time spread for the full photocathode illumination, the relative collection efficiency as a function of the voltage between photocathode and focusing electrode, were measured and are discussed, particularly with respect to the optimization of photomultiplier operating conditions for timing applications. Measurements were also made on the photomultiplier´s high repetition rate counting performance as well as the rate dependent photomultiplier gain.