Plasma temperature dynamics provide significant insight when evaluating ion source performance. Quantities such as beam emittance, or mean transverse energy, are strongly correlated with the source plasma temperature. At LANSCE there is currently no method implemented for measuring initial source emittance or implementing tunability of mean transverse energy through ion source control parameters. In this work we will discuss our demonstration of a new laser diagnostic tool for measuring H- beam emittance on the LANSCE H- ion source laser diagnostic stand. Our investigated method will be an extension of systems outlined for NIFS, and will be optimized for rapid response times, scanning the Doppler broadened Hydrogen-alpha emission line at a rate 10x faster than the plasma ignition time window (800 microseconds). We will show that our real-time, non-intrusive measurement approach will enable characterization and study of source control parameter effects on source plasma temperature for future emittance optimization.

Photocathodes play key roles in supplying electron beams for diverse research facilities. Among them, semiconductor photocathodes stand out for their high quantum efficiency (QE). Typically, a high QE, long operation time, low thermal emittance and fast response time are desired for the accelerator community. However, the performance of semiconductor photocathodes is extremely sensitive to growth conditions. In this presentation, I will delve into recent advancements in semiconductor photocathodes fabrication at Applied Cathode Enhancement and Robustness Technologies (ACERT) of Los Alamos National Laboratory (LANL). These updates allow us to fine tune growth parameters and fabricate photocathodes with high QE and low emittance at high gradient to meet the requirements of photocathodes for Cathodes and Radiofrequency Interactions in Extremes (CARIE) project at LANL. Specifically, I will highlight our progress in developing a control system that enables to accurately control growth parameters. Furthermore, I will show our preliminary results focusing on the fabrication of CsSb and CsTe photocathodes using both sequential and co-deposition methods.

High frequency RF guns cryogenically cooled to liquid nitrogen temperatures or lower offer potential for extreme accelerating electric fields exceeding 250 MV/m at the cathode. This can result in enormous increase in the brightness of electron beams obtained from RF guns but can be challenging to integrate high QE photocathodes. This talk will detail the efforts at LANL towards the realization of such a gun and possibly the first field and beam results from a C band room temperature gun.