A comparison of SNS internal and external antenna source performance with and without cesium.

Experiments comparing an internal and an external antenna H source at the Spallation Neutron Source with and without cesium revealed key performance differences which provide insight to the source physics and will guide the development of an RF H source at the ISIS Neutron Source. RF power sweeps were taken for each of these cases, for which the total charge, electron to H ratio, and H extracted per kW are all studied and plotted. At around 40 kW and typical hydrogen flow and cooling parameters, cesiated sources output 35 mA square beam pulses where uncesiated sources output 15 mA.

Upgrading the LANSCE accelerator with a SNS RF-driven H ion source.

The LANSCE accelerator is currently powered by a filament-driven, biased converter-type H ion source that operates at 10%, the highest plasma duty factor for this type of source, using only ∼2.2 SCCM of H. The ion source needs to be replaced every 4 weeks, which takes up to 4 days.

Installation and commissioning of the ion source systems for the new spallation neutron source 2.5 MeV injector.

The U.S. Spallation Neutron Source (SNS) is a state-of-the-art neutron scattering facility delivering the world's most intense pulsed neutron beams to a wide array of instruments, which are used to conduct investigations in many fields of engineering, physics, chemistry, material science, and biology.

The status of the SNS external antenna ion source and spare RFQ test facility.

The Oak Ridge National Laboratory operates the Spallation Neutron Source, consisting of a H(-) ion source, a 1 GeV linac and an accumulator ring. The accumulated <1 μs-long, ∼35 A beam pulses are extracted from the ring at 60 Hz and directed onto a liquid Hg target. Spalled neutrons are directed to ∼20 world class instruments.

Characterization of the CW starter plasma RF matching network for operating the SNS H⁻ ion source with lower H₂ flows.

The Spallation Neutron Source H(-) ion source is operated with a pulsed 2-MHz RF (50-60 kW) to produce the 1-ms long, ∼50 mA H(-) beams at 60 Hz. A continuous low power (∼300 W) 13.56-MHz RF plasma, which is initially ignited with a H2 pressure bump, serves as starter plasma for the pulsed high power 2-MHz RF discharges.