Quantum efficiency and thermal emittance of metal photocathodes

Thermal emittance and response time measurements of negative electron affinity photocathodes

The thermal emittance and temporal response of a photocathode set an upper limit on the maximum achievable electron beam brightness from a photoemission electron source, or photoinjector. We present measurements of these parameters over a broad range of laser wavelength for two different negative electron affinity NEA photocathodes. The thermal emittance of NEA GaAs and GaAsP has been measured ...

Effect of Roughness on Emittance of Potassium Cesium Antimonide Photocathodes*

Here we present first measurements of the effect of roughness on the emittance of K2CsSb photocathodes under high fields. We show that for very thin cathodes the effect is negligible at up to 3 MV/m but for thicker and more efficient cathodes the effect becomes significant. We discuss ways to modify the deposition to circumvent this problem.

Preparation/Characterization of Atomically Flat and Clean Mo (100) Surfaces and Thermal Emittance/Response Time Measurements of Cs3Sb Photocathodes

Solar Reflectance and Thermal Emittance

The solar reflectance and the thermal emittance of a roof surface are important surface properties affecting the roof temperature, which, in turn, drives the heat flow through the roof. The solar reflectance (p) determines the fraction of the solar radiation incident from all directions that is diffusely reflected by the surface. The thermal emittance (c) describes how well the surface radiates...

Fabrication and Measurement of Cesiated Metal Photocathodes

Title of Thesis: FABRICATION AND MEASUREMENT OF CESIATED METAL PHOTOCATHODES Nathan A. Moody, Master of Science, 2004 Thesis Directed By: Professor Patrick O’Shea Department of Electrical and Computer Engineering A requirement for accelerator applications such as free electron lasers is a high current, high quality electron beam. This is achieved using a photoinjector, where a drive laser modul...