Variation of The Photoelectric Effect with Temperature and Determination of the Long Wave-length Limit for Tungsten

The photoelectric characteristics of a tungsten surface have been studied from room temperature to 1140^∘{}K. It has been found necessary to use a tube of glass and quartz, and to seal it off the pumps after a thorough outgassing. The surface is rendered insensitive at room temperature by traces of gas, but regains its sensitivity between 800 and 900^∘{}K. The long wave-limit was found to be 2570±{}50A, and was independent of temperature.