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Anderson, S.

Publications and source records attributed to Anderson, S..

The Compelling Need for a Mid-Scale Stellarator Facility

In the pursuit of the goal of commercial fusion as an abundant and safe source of energy, the stellarator is a leading concept with compelling attractiveness and demonstrated performance. In this white paper we, as a community of US researchers from Universities, National Laboratories, and Private Industry, involved in studying the stellarator concept, lay out the programmatic and technical motivation for a new mid-size stellarator research facility in the US. This contribution is complementary to several other whitepapers authored by members of our community which address different mid-scale stellarator aspects. A community based technical facility proposal has been prepared by F. Parra, et al: Flexible Stellarator Physics Facility. Two private stellarator companies have submitted proposals supporting the development of a mid-scale stellarator: Thea Energy (C.P.S. Swanson, et al.), Type One Energy (W. Guttenfelder, et al.).

70 PLASMA PHYSICS AND FUSION TECHNOLOGY

The Compelling Need for a Mid-Scale Stellarator Facility

In the pursuit of the goal of commercial fusion as an abundant and safe source of energy, the stellarator is a leading concept with compelling attractiveness and demonstrated performance. A new mid-size stellarator is needed to retire risks and innovate towards a high performance, economically attractive, stellarator Fusion Pilot Plant. In this presentation we, as a community of US researchers from Universities, National Laboratories, and Private Industry, involved in studying the stellarator concept, lay out the programmatic and technical motivation for a new and modern mid-size stellarator research facility. A new mid-scale stellarator is needed to realize the potential predicted by a solid body of theory and simulation along with advances in computational tools for optimization and non-linear turbulence modeling. Notably, it is possible to combine the advantages of the stellarator (steady state, no current drive, no disruptions) with the good confinement regularly achieved in tokamaks. The top priorities for experimental work, and the motivation for a mid-scale stellarator experiment are: turbulence control, non-resonant divertor, MHD stability at large beta, confinement of fast particles, and coil simplification. A new mid-size quasi-symmetric stellarator, built as a user facility, would complement existing research at Wendelstein 7-X and LHD and strongly augment private industry. It would provide a program of innovative research, concept validation, theoretical advancement, and workforce development. Growing support and interest for stellarators by the fusion community and private industry affirms this rationale.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY

Downselection of Landing Sites for the Mars Exploration Rovers

Six landing sites that show evidence for processes involving water have been selected from a possible 185 for the Mars Exploration Rovers. These sites are being imaged by orbiting spacecraft and evaluated for science potential and safety before selection of two in May 2002. Additional information is contained in the original extended abstract.

Golombek, M.

Single Event Upset Effects on the Clementine Solid State Data Recorder

The sensitivity of the Clementine 2.1 Gbit Solid State Data Recorder (SSDR) to single event upsets was characterized in ground tests. Subsequent in-situ measurements of the ambient radiation environment by experiments on-board Clementine permitted evaluation of the ability of models of the single event phenomenon in the SSDR to be tested using actual data. Initial results from the analysis reveal a nearly constant background upset rate of ~71 bit flips/day for the SSDR. There is no obvious correlation with a solar proton event recorded by Clementine and several other spacecraft on 20-21 February 1994, indicating that the SSDR was not sensitive to protons. The constant rate is thus interpreted as being a function of the Galactic Cosmic Ray heavy ion environment. A pronounced lunar orbit altitude dependence has also been identified in the data though the cause has not yet been unambiguously identified.

Clementine

Calibration of a mass spectrometer experiment for ozone

A system with which to calibrate a stratospheric mass spectrometer experiment for ozone has been developed and evaluated. The stability of ozone and the formation of impurities within the calibration volume were measured. The half-life of ozone is about 12 hours, its purity ranges from 95% to 99% and is known to within 1%. The total calibration accuracy of the mass spectrometer experiment for ozone is about + or - 2%.

Anderson, S.

A comparison of ozone measurements

A mass spectrometer beam experiment and a UV absorption instrument (modified Dasibi instrument) have simultaneously measured ozone mixing ratios in the stratosphere (20-40 km). Both experiments were independently calibrated using absolute standards. The ozone profiles obtained during three balloon descents are in excellent agreement; fine structures are resolved by both experiments. The RMS uncertainty in ozone mixing ratios is about 3% for either instrument.

Mauersberger, K.