Dynamical Processes in the Work Function of a Thermionic Cathode

Jonathan Edelen, RadiaSoft LLC (Principal Investigator)

Yine Sun, Argonne National Laboratory (Co-Investigator)

The objective of this project is to develop new tools for understanding the dynamical processes in thermionic cathode RF electron guns. Recent work has developed models that seek to understand steady state dynamics of the cathode work function based on our physical understanding of evaporation, sputtering, and recovery of the cathode surface coating. Our project will improve upon these studies by measuring the temperature and output current as a function of different gun configurations. We will utilize fresh cathodes and a systematic evaluation of these cathodes in repeatable environments. This will enable the development of improved computational models in addition to shedding new light on the interplay between ion bombardment, electron bombardment, and system configurations on the expected output current of a thermionic RF gun. We will then utilize these tools to provide a more accurate estimation of the thermionic cathode lifetime in RF environments.