Document Type

Conference Paper

Publication Date




Publication Title

Proceedings of the North American Particle Accelerator Conference



Conference Name

North American Particle Accelerator Conference (5th), August 7-12, 2022, Albuquerque, New Mexico


Polarized electrons from GaAs photocathodes have been key to some of the highest-impact results of the Jefferson Lab science program over the past 30 years. During this time, various studies have given insight into improving the operational lifetime of these photocathodes in DC high-voltage photo-guns while using lasers with spatial Gaussian profiles of typically 0.5 mm to 1 mm FWHM, cathode voltages of 100 kV to 130 kV, and a wide range of beam currents up to multiple mA. In this contribution, we show recent experimental data from a 100 kV to 180 kV setup and describe our progress at predicting the lifetime based on the calculable dynamics of ionized gas molecules inside the gun. These new experimental studies at Jefferson Lab are specifically aimed at exploring the ion damage of higher-voltage guns being built for injectors.


Published by JACoW Publishing under the terms of the Creative Commons Attribution 4.0 International license (CC BY 4.0). Any further distribution of this work must maintain attribution to the authors, the published article's title, publisher, and DOI.

Original Publication Citation

Bruker, M., Grames, J., Hernández-García, C., Poelker, M., Zhang, S., Lizárraga-Rubio, V., Valerio-Lizárraga, C., & Yoskowitz, J. T. (2022). New results at JLab describing operating lifetime of GaAs photo-guns. In S. Biedron, E. Simakov, S. Milton, P.M. Anisimov, & V.R.W. Schaa (Eds.) Proceedings of the North American Particle Accelerator Conference (pp.644-647). JACOW.


0000-0003-1792-6603 (Yoskowitz)