The Effect of Temperature on the Energy Distribution of Photoelectrons. I. Normal Energies

An experimental test has been made of DuBridge's theory of the distribution of normal energies of photoelectrons. With a modified parallel-plate method of analysis, photoelectrons were ejected from a strip of Mo foil which could be held at any desired temperature. Current-voltage curves for temperatures from 300° to 965°K show a good agreement with the theory. From the shifts required to fit the experimental and theoretical curves the values of $V_{max}$ at 0°K can be determined. For any fixed temperature these values of $V_m$ fit the Einstein equation, and for a fixed wave-length they are independent of $T$, as required by the theory.