Quantifying the Cesium and H- Densities Inside the LANSCE H- Ion Source with Laser Absorption Techniques

4 Sep 2020, 16:20
20m
Oral H– and D– sources for fusion, accelerators and other applications H– sources for accelerators: Oral session O3

Speaker

David Kleinjan (Los Alamos National Laboratory)

Description

The Los Alamos Neutron Science Center (LANSCE) H- ion source (LHIS) has provided stable output for decades of LANL mission needs. While operationally well understood, the internal relationship between the LHIS plasma, cesium distribution (the catalyst for producing H- ions), and produced H- beam remains a mystery, only explored indirectly with models.

We will develop fast, accurate, and non-invasive diagnostics techniques to measure the Cs and H- densities inside LHIS. These diagnostics are based on optical absorption spectroscopy that have been developed in the last decade for fusion based H- ion sources that can readily be applied to the accelerator based LHIS. A refined form of optical absorption spectroscopy, the laser absorption technique (LAT), utilizes lasers tuned to a given atomic species to measure its density. In this case a laser tuned to the D2 line of cesium will be used to determine its density inside LHIS. Similarly, a refined version of LAT called the cavity ring-ring down spectroscopy (CRDS) technique utilizes a laser tuned to H- photo-detachment to measure the H- densities at inside LHIS.

With successful development of these diagnostic techniques, any hidden or dormant capabilities in LHIS will be found and capitalized upon, both in its modeling and operation. Also, its potential benefit to LANSCE and LANL future needs will be realized. More generally, this will be the first use of these plasma diagnostic techniques on an accelerator based H- ion sources. We will present on the preliminary status of the diagnostic setup.

Primary author

David Kleinjan (Los Alamos National Laboratory)

Co-authors

Levi Rouleau (Los Alamos National Laboratory) Gary Rouleau (Los Alamos National Laboratory)

Presentation Materials

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