RELATIONSHIP BETWEEN THE RESIDUAL GAS PRESSURE AND THE LOWEST TEMPERATURE KEEPING METAL SURFACES ESSENTIALLY CLEAN IN HIGH VACUA

摘要

Effective work functions for thermal positive ionic and electronic emissions from heated metal surfaces were measured, from the data on which the lowest surface temperatures (T*) keeping each surface atomically clean were determined to be about 1990, 1970 and 1710 K for Mo, Wand Re, respectively, in the residual gas pressure (P) of about 2 x 10(-5) Pa The data obtained with Re at P approximate to 10(-5)-10(-3) Pa yielded T* = 2820+241 log P. [References: 5]