11 research outputs found
Recommended from our members
Multi-kiloampere, electron-beam generation using metal photo-cathodes driven by ArF and KrF lasers
An electron-beam-pumped laser operating at ArF (193 nm) or KrF (248 nm) producing 35 MW (3.5 J in 100 ns) has been used to illuminate a micro-machined aluminum cathode. The cathode was pulsed to 2.75 MV at fields of 185 kV/cm (15-cm AK gap) using REX[1,2](a 4-MV, 5-kA,85-ns) pulsed-diode machine. The extracted current versus incident laser power, and therefore, quantum efficiency was measured for KrF at 5x10{sup -5}; ArF was significantly higher at 1x10{sup -3}. Current densities of 100 A/cm{sup 2} and total currents of 2 kA have been achieved, the latter by increasing the cathode area in proportion to the laser power
Recommended from our members
Position measurements for the isotope production facility and the switchyard kicker upgrade projects
The Los Alamos Neutron Science Center (LANSCE) is installing two beam lines to both improve operational tuning and provide new capabilities within the facility. The Isotope Production Facility (IPF) will provide isotopes for medical purposes by using the H' beam spur at 100 MeV and the Switchyard Kicker Upgrade (SYK) will allow the LANSCE 800-MeV H beam to be rapidly switched between various beam lines within the facility. The beam position measurements for both of these beam lines uses a standard micro-stripline beam position monitor (BPM) with both a 50-mm and 75-mm radius. The cable plant is unique in that it unambiguously provides a method of verifying the operation of the complete position measurement. The processing electronics module uses a log ratio technique with error corrections such that it has a dynamic range of -12 dBm to -85 dBm with errors less than 0.15 dB within this range. This paper will describe the primary components of these measurement systems and provide initial data of their operation
Recommended from our members
Ion source development for the Los Alamos heavy ion fusion injector
A multi-beam injector is being designed and built at Los Alamos for the US Heavy Ion Fusion Program. As part of this program, development of an aluminum-spark, pulsed plasma source is being carried out. Faraday cup diagnostics are used to study current emission and to map the current profile. An aluminum oxide scintillator with photographic film is used in conjunction with a pepper-pot to obtain time integrated emittance values
Recommended from our members
Progress on the Los Alamos heavy-ion injector
Heavy-ion fusion using an induction linac requires injection of multiple high-current beams from a pulsed electrostatic accelerator at as high a voltage as practical. Los Alamos National Laboratory is developing a 16-beam, 2-MeV, pulsed electrostatic accelerator for Al/sup +/ ions. The ion source will use a pulsed metal vapor arc plasma. A biased grid will control plasma flux into the ion extraction region. This source has achieved a normalized emittance of epsilon/sub n/ < 3.10/sup -7/..pi..-m-rad with Al/sup +/ ions. An 800 kV Marx prototype with a laser fired diverter is being assembled. The ceramic accelerating column sections have been brazed and leak tested. Voltage hold off on a brazed sample was more than doubled by selective removal of the Ticusil braze fillet extending along the ceramic. A scaled test module held 250 kV for 50 ..mu..s, giving confidence that the full module can hold 175 kV per section. The pressure vessel should be received in June 1986. High-voltage testing of a 1 MV column will begin by early 1987
POSITION MEASUREMENTS FOR THE ISOTOPE PRODUCTION FACILITY AND THE SWITCHYARD KICKER UPGRADE PROJECTS
Recommended from our members
Pulsed power systems for the DARHT accelerators
The Dual-Axis Radiographic Hydro Test (DARHT) Facility is being designed to produce high-resolution flash radiographs of hydrodynamics experiments. Two 16- to 20-MeV linear induction accelerators (LIA), with an included angle of 90{degree}, are used to produce intense bremsstrahlung x-ray pulses of short duration (60-ns flat-top). Each accelerator has a 4-MeV electron source that injects an electron beam into a series of 250-kV induction cells. The three major pulsed-power systems are the injectors, the induction-cell pulsed-power (ICPP) units, and the ICPP trigger systems, and are discussed in this paper. 11 refs., 5 figs, 3 tabs
Recommended from our members
EXPERIENCE WITH THE LOW ENERGY DEMONSTRATION ACCELERATOR (LEDA) HALO EXPERIMENT BEAM INSTRUMENTATION
A 52 quadrupole-magnet FODO lattice has been assembled and operated at the Los Alamos National Laboratory. The purpose of this lattice is to provide a platform to measure the resulting beam halo as the first few magnets of the lattice produce various mismatch conditions. These data are then compared with particle simulation so that halo formation mechanisms may be better understood. The lattice is appended to the LEDA 6.7-MeV radio frequency quadrupole (RFQ) and is followed by a short high-energy beam transport (HEBT) that safely dumps the beam into a 670-kW beam stop