since
November 1, 2003
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Stellarator News |
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The Stellarator News is an international newsletter created by and for the stellarator community. Articles are submitted electronically to the editor who creates each issue using Adobe FrameMaker.
Stellarator News appears every other month. Back issues are available in Adobe PDF format. Version 3.0 (or higher) of Acrobat is required.
To view and print these files, you may download a free Adobe
Acrobat
Reader. 
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at the National Institute for Fusion Science in Toki, Japan |
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Issue
Number
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Date
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HTML
Version
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PDF
Version
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| 89 | November 2003 | HTML | |
| 88 | September 2003 | HTML | |
| 87 | May 2003 | HTML | |
| 86 | March 2003 | HTML | |
| 85 | January 2003 | HTML | |
| 84 | November 2002 | HTML | |
| 83 | September 2002 | HTML | |
| 82 | July 2002 | HTML | |
| 81 | May 2002 | HTML | |
| 80 | March 2002 | HTML | |
| 79 | January 2002 | HTML | |
| 78 | November 2001 | HTML | |
| 77 | September 2001 | HTML | |
| 76 | July 2001 | HTML | |
| 75 | May 2001 | HTML | |
| 74 | March 2001 | HTML | |
| 73 | January 2001 | HTML | |
| 72 | November 2000 | HTML | |
| 71 | September 2000 | HTML | |
| 70 | July 2000 | HTML |
Orbits are considered in conventional stellarators (i.e. with
helical coils) using Boozer coordinates. The Advanced Toroidal Facility
(ATF) in Oak Ridge, Tennessee, will be used as an example to study the
effects of its configurational flexibility on orbit topology. It is
shown that the symplectic integration technique yields superior results
for single particle orbits. These orbits will be compared with
predictions using the J* invariant. J* conservation
allows examination and understanding of the global stellarator
topology, both with and without radial electric fields.
Large stellarator research programs are being pursued in Europe and Japan (>$1 billion in new facilities). These programs are important because the similarities and differences between stellarators and tokamaks can be used both to improve our understanding of toroidal confinement and to develop an improved reactor concept. Stellarators have performance similar to that of comparable tokamaks. New large stellarator experiments under construction with superconducting coils will have parameters comparable to those of present tokamaks. Significant experimental and theoretical progress has been made in understanding transport, finite-beta behavior in three-dimensional toroidal geometry, and concept improvement. Ideas to further improve the stellarator concept will be tested in new experiments. Recent studies have improved the stellarator reactor concept and shown that stellarators can be competitive with tokamaks as reactors.
U.S. Stellarator Proof of Principle Program (in PDF format)
An integrated program with mutually supporting elements is proposed
to develop the physics basis for high-beta good-confinement
stellarators with low plasma aspect ratio that could lead to more
compact stellarator reactors. The program consists of: (1) a new
"proof-of-principle" facility, the National Compact Stellarator
Experiment (NCSX); (2) a new concept exploration experiment, the
Quasi-Omnigeneous Stellarator (QOS); (3) the existing Helically
Symmetric Experiment and an upgrade to the Compact Auburn Torsatron;
(4) stellarator theory focusing on concept optimization and key
stellarator physics issues; (5) collaboration with the international
stellarator program in specific areas; and (6) system studies to guide
concept optimization tradeoffs. The two new elements of the
proposed program are based on promising transport optimization
strategies for compact stellarators: quasiaxisymmetry (NCSX) and
quasiomnigeneity (QOS); each has distinct complementary advantages
(physics, reactor embodiment). Determination of the optimum
approach to pursue is a goal of the US stellarator program.
U.S. Stellarator Program — Opportunities for Concept Improvement (July 1999, in PDF format)
The U.S. stellarator community presented a "White Paper" at the 2-week July 1999 Fusion Summer Study at Snowmass, Colorado outlining a proposed increased U.S. stellarator program. The White Paper discusses: (1) advanced toroidal confinement approaches; (2) compact stellarators; (3) stellarator research opportunities; (4) the proposed National Compact Stellarator Experiment (NCSX); (5) the proposed Quasi-Omnigeneous Stellarator (QOS); (6) the existing Helically Symmetric Experiment (HSX); (7) an upgrade to the Compact Auburn Torsatron (CAT-U); (8) international collaboration; and (9) system studies.
Preliminary
Announcement 13th International Stellarator Workshop
24-28 September, 2001 - Canberra Australia
U.S.-Japan Workshop on Helical System Concept Improvement
A US-Japan Workshop on Helical System Concept Improvement was held in Oak Ridge, Sept. 23–24, 1999. 24 papers were presented by participants from Japan, Germany, Spain, Australia, and the U.S. The focus was on new stellarator concepts and the physics relevant to them. The magnetic configurations discussed in most detail were quasi-axisymmetric stellarators, quasi-omnigeneous stellarators, and helical axis stellarators.
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Australian National University - H-1. |
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Max Planck Institut für Plasma Physik, Garching, Germany - Wendelstein 7-AS and Wendelstein 7-X. |
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Auburn University - Compact Auburn Torsatron (CAT). |
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Torsatron Stellarator Laboratory of the University of Wisconsin, Madison - Helically Symmetric Experiment (HSX). |
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National Institute for Fusion
Science, Nagoya, Japan Large Helical Device (LHD). MPEG movie (600kbyte) of an LHD
shot. |
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Asociación EURATOM-CIEMAT para Fusión - TJ1U Stellarator and TJII Heliac. |
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The National Compact Stellarator Experiment (NCSX) |
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QPS - An Experiment to Explore the Quasi-Poloidal Approach to Compact Stellarators |
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Compact Helical System (CHS). |
