PAC09 - List of Authors (Greenway, W.G.)

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Greenway, W.G.

Paper	Title	Page
MO6RFP033	Development of a Li+ Alumino-Silicate Ion Source	426
	P.K. Roy, A. Anders, W.G. Greenway, J.W. Kwan, S.M. Lidia, P.A. Seidl, W.L. Waldron LBNL, Berkeley, California
	Funding: This work was supported by the Director, Office of Science, Office of Fusion Energy Sciences, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. To uniformly heat targets to electron-volt temperatures for the study of warm dense matter, one strategy is to deposit most of the ion energy at the peak of energy loss (dE/dx) with a low (E < 5 MeV) kinetic energy beam and a thin target. Lower mass ions have a peak dE/dx at a lower kinetic energy. To this end, a small lithium (Li+) alumino-silicate source has been fabricated, and its emission limit has been measured. These surface ionization sources are heated to {10}00-1150 C where they preferentially emit singly ionized alkali ions. Alumino-silicates sources of K+ and Cs+ have been used extensively in beam experiments, but there are additional challenges for the preparation of high-quality Li+ sources: There are tighter tolerances in preparing and sintering the alumino-silicate to the substrate to produce an emitter that gives uniform ion emission, sufficient current density and low beam emittance. We report on recent measurements of high ( up to 35 mA/cm²) current density from a Li+ source. Ion species identification of possible contaminants is being verified with a Wien (E x B) filter, and via time-of-flight. J.J. Barnard et al., Nuclear Instruments and Methods in Physics Research A 577 (2007) 275283.

Paper

Title

Page

MO6RFP033

Development of a Li+ Alumino-Silicate Ion Source

426

P.K. Roy, A. Anders, W.G. Greenway, J.W. Kwan, S.M. Lidia, P.A. Seidl, W.L. Waldron
LBNL, Berkeley, California

Funding: This work was supported by the Director, Office of Science, Office of Fusion Energy Sciences, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231.

To uniformly heat targets to electron-volt temperatures for the study of warm dense matter, one strategy is to deposit most of the ion energy at the peak of energy loss (dE/dx) with a low (E < 5 MeV) kinetic energy beam and a thin target*. Lower mass ions have a peak dE/dx at a lower kinetic energy. To this end, a small lithium (Li+) alumino-silicate source has been fabricated, and its emission limit has been measured. These surface ionization sources are heated to {10}00-1150 C where they preferentially emit singly ionized alkali ions. Alumino-silicates sources of K+ and Cs+ have been used extensively in beam experiments, but there are additional challenges for the preparation of high-quality Li+ sources: There are tighter tolerances in preparing and sintering the alumino-silicate to the substrate to produce an emitter that gives uniform ion emission, sufficient current density and low beam emittance. We report on recent measurements of high ( up to 35 mA/cm²) current density from a Li+ source. Ion species identification of possible contaminants is being verified with a Wien (E x B) filter, and via time-of-flight.

*J.J. Barnard et al., Nuclear Instruments and Methods in Physics Research A 577 (2007) 275283.