Design and operation of a 50 MeV Electron Linear Accelerator utilizing a low emittance ( 7 c 5 to 10 mm-mrad) radio-frequency gun operating at an output energy of 5 MeV and a charge of 1 nC is described. Design calculations and early radio-frequency measurements and operational experience with the electron gun utilizing a dummy copper cathode in place of the proposed photocathode emitter are gi...

The National Synchrotron Light Source (NSLS) at Brookhaven National Laboratory (BNL) is considering an upgrade based on the Photoinjected Energy Recovering Linac (PERL). The various injector schemes for this machine are being extensively investigated at BNL. One of the possible options is photocathode DC gun. The schematic layout of a PERL DC gun based injector and its preliminary beam dynamics...

Interface modification with para -aminobenzoic acid passivated the interface states, causing rapid photoelectron transport through Sb 2 Se 3 /TiO and resulting in high onset potential photocurrent density photocathode for photoelectrochemical water splitting. • Surface defects limit photovoltage development. not only passivates but also allows transport. Record-high potential, density, half-cel...

DOI: 10.1002/adsu.201700142 chemical fuels became an alternative path for the search of clean energy sources.[1] Therefore, a diverse class of semiconductor photoelectrodes and nonprecious catalytic materials has been investigated for solar water splitting.[2–5] Only a few semiconductor photocathodes and noble metal-free catalysts showed encouraging solar water splitting performances for hydrog...

We present the results of numerical calculations of the effects of noise, slippage and superradiance in the UCLA infrared (IR) free electron laser (FEL). The experiment, which uses a high brightness electron beam produced by a photocathode RF gun and a 1.5 cm period planar undulator, will compare the FELevolution starting from noise to that starting from an input signal . Numerical studies indi...

A sealed gas photon detector with a GEM (Gas Electron Multiplier) cascade coupled to a semitransparent CsI photocathode has been studied. High gains, reaching 10, and fast anode signals, of a width of 15 ns, were obtained with this GEM-Photomultiplier in Ar/CH4 (95/5), in a photon counting mode. The life-time of this first prototype detector under high photon flux and large anode currents is pr...

We advocate support of research aimed at developing alternatives to the photomultiplier tube for photon detection in large astroparticle experiments such as gamma-ray and neutrino astronomy, and direct dark matter detectors. Specifically, we discuss the development of large area photocathode microchannel plate photomultipliers and silicon photomultipliers. Both technologies have the potential t...

p-type NiO nanofibers have been synthesized from a simple electrospinning and sintering procedure. For the first time, p-type nanofibers have been electrospun onto a conductive fluorine doped tin oxide (FTO) surface. The properties of the NiO nanofibers have been directly compared to that of bulk NiO nanopowder. We have observed a p-type photocurrent for a NiO photocathode fabricated on an FTO ...

Amplified square shaped picosecond pulses was generated for low emittance electron beam generation in a photocathode RF-GUN. Square shaped pulses were generated by using Ti:sapphire amplifier system in inrfared region and then converted to ultraviolet region via third harmonics generation. Generated squares shaped pulses were measeured by crosscorrelation and spectral interferometric technique ...

At the Argonne Chemistry Division efforts are underway to develop a sub-picosecond electron beam pulse radiolysis facility for chemical studies. The target output of the accelerator is to generate electron pulses that can be adjusted from 3nC in .6ps to 100nC in 45ps. In conjunction with development of the accelerator a stateof-the-art ultrafast laser system is under construction that will driv...