In order to provide maximum physics benefits, the International Linear Collider (ILC) must have a highly polarized electron beam with a low emittance. High electron spin -polarization (>85%) is attainable with a modern GaAs photocathode illuminated by a circularly polarized laser. Low emittance is achievable with an rf photoinjector, and can be further improved with a round-to-flat beam transfo...

Ultrafast electron-based coherent radiation sources, such as free-electron lasers (FELs), ultrafast electron diffraction (UED) and Thomson-scattering sources, are becoming more important sources in today's ultrafast science. Photocathode laser is an indispensable common subsystem in these sources that generates ultrafast electron pulses. To fully exploit the potentials of these sources, especia...

We report results of a systematic study of the operational characteristics of a single-step parallel-plate avalanche chamber with CsI photocathode under high-gain conditions at room temperature and 1 atm pressure. Different mixtures of He and Ar with hydrocarbons were tested, as well as with ethylferrocene vapor which are known to form an adsorbed photosensitive layer on the Csl photocathode. T...

The rapidly increasing global demand for energy combined with the environmental impact of fossil fuels has spurred the search for alternative sources of clean energy. One promising approach is to convert solar energy into hydrogen fuel using photoelectrochemical cells. However, the semiconducting photoelectrodes used in these cells typically have low efficiencies and/or stabilities. Here we sho...

In the past few years a readout for Ring-Imaging Cherenkov (RICH) detectors [1] based on CsI photocathodes has been under intensive development [2-15] . The detector is a parallel-plate avalanche chamber (PPAC) with a UV-sensitive solid-CsI photocathode separated by a narrow gap (1-2 mm) from a wire-mesh anode plane (or wire anode plane as in ref. [4]) . The Cherenkov light generated in a radia...

The bERLinPro project, a small superconducting RF (SRF) c.w. energy recovery linac (ERL) is being built at Helmholtz-Zentrum Berlin in order to develop the technology required for operation of a high current, 100 mA, 50 MeV ERL. The electron source for the accelerator is a 1.4 cell SRF photoinjector fitted with a multi-alkali photocathode. As part of the HZB photoinjector development program th...