Variation of Time-of-Flight of Electrons Through a Photomultiplier*

A new experimental method utilizing a property of the gas laser has been developed that permits the measurement of the variation of the time of flight of electrons through a photomultiplier as a function of the position on the cathode from which they are emitted. The measurement of time variation is accomplished by comparing it with the distance traveled by a light beam during the same time and is capable of a time resolution of approximately 10−11 sec.