Micro-channel plate (MCP)-based photodetectors are capable of picosecond level time resolution and sub-mm level position resolution, which makes them a perfect candidate for the next generation large area photodetectors. The large-area picosecond photodetector (LAPPD) collaboration is developing new techniques for making large-area photodetectors based on new MCP fabrication and functionalization methods. A small single tube processing system (SmSTPS) was constructed at Argonne National Laboratory (ANL) for developing scalable, cost-effective, glass-body, 6 cm × 6 cm, picosecond photodetectors based on MCPs functionalized by Atomic Layer Deposition (ALD). Recently, a number of fully processed and hermitically sealed prototypes made of MCPs with 20 m pores have been fabricated. This is a significant milestone for the LAPPD project. These prototypes were characterized with a pulsed laser test facility. Without optimization, the prototypes have shown excellent results: The time resolution is ~57 ps for single photoelectron mode and ~15 ps for multi-photoelectron mode; the best position resolution is ≤ 0.8 mm for large pulses. In this paper, the tube processing system, the detector assembly, experimental setup, data analysis and the key performance will be presented.

A thin film coating of titanium nitride was applied to the surface of rf cavity tuners to reduce secondary electron generated when the existing copper base material is in place. The tuners are used in high-field gradients, where electron heating of the tuner is a problem. By reducing the generation of electrons the temperature of the tuners will be reduced, for better reliability. This paper compares characteristics useful for rf cavity tuners, such as surface composition and secondary electron yield, for copper, titanium-coated copper, and titanium-nitridecoated copper. The process and the setup of equipment used to apply the coatings are summarized.

In this article, the design, fabrication, prepolish coating, and polishing of a reaction-bonded (RB) internally cooled silicon carbide (SiC) mirror is described. The mirror was developed from a mold of SiC powder in a near-net shape and then infused with silicon vapor to make a dense mirror substrate. The mirror surface was then rough polished, coated with a thin layer of SiC, and polished to a final fine finish. The design and manufacturing of this mirror—intended to be used as a multilayer substrate on a high-heat-load undulator beamline—are described, and data on the surface figure and finish are provided. This type of mirror can provide an attractive alternative to internally cooled silicon mirrors. Because the substrate is made in one piece, it avoids the frit or metal bonding that is usually necessary with silicon substrates. Advantages of RB SiC mirrors include lower cost and higher reliability.

Construction of a single-pass free-electron laser (EEL) based on the self-amplified spontaneous emission (SASE) mode of operation is nearing completion at the Advanced Photon Source (APS) with initial experiments imminent. The Al% SASE FEL is a proof-of-principle fourth-generation light source. As of January 1999 the undulator hall, end-station building, necessary transfer lines, electron and optical diagnostics, injectors, and initial undulatory have been constructed and, with the exception of the undulatory, installed. All preliminary code development and simulations have also been completed. The undulator hall is now ready to accept first beam for characterization of the output radiation. It is the project goal to push towards fill FEL saturation, initially in the visible, but ultimately to W and VUV, wavelengths,

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