Three hundred fusion researchers gathered in Snowmass, Colorado, for the two week 1999 Fusion Summer Study, July 11 - 23 (FPN99-30).

During the opening, plenary session, Summer Study co-chair Mike Mauel (Columbia University) told the group that we had "come together to develop a scientific and technical basis for consensus on (1) the key issues for plasma science, technology, and energy and environment for fusion energy development, and (2) the opportunities and potential contributions of existing and possible future facilities and programs to reduce fusion development costs and achieve attractive economic and environmental features."

The Study was organized into six topical Discussion Groups, three meeting in the mornings and three in the afternoons, with frequent breakout subgroups under each. The three morning groups were on the themes Magnetic Fusion Concepts, Inertial Fusion Concepts, and Emerging Fusion Concepts. The three afternoon groups were on Plasma Science Issues, Technology Issues, and Energy Issues.

On the last morning, leaders of the six groups presented the results of their respective discussions. The vugraphs from these presentations are posted on the web at: http://www.ap.columbia.edu/fusion/snowmass/WG_Summaries.html

Press write-ups on the workshop have appeared in Nature (July 29) and Science (August 6). In the Nature article, writer Colin Macilwain said, "Scientists at the meeting agreed (on) general priorities for the various branches of the programme. Perhaps most significantly, they backed a statement that the tokamak is "technically ready for a high-gain burning-plasma experiment" -- overwhelmingly rejecting a plea from theorists to qualify this language." In the Science article, writer James Glanz says, "After decades of division, researchers meeting in the Rockies found some surprising overlap in approaches as different as laser and magnetic fusion." He said, "Included were proponents of fresh new concepts as well as old reliables; nitty-gritty technologists sat cheek-by-jowl with basic scientists."

Tony Taylor (General Atomics) presented the summary of the Magnetic Fusion Concepts Working Group at the final plenary. He said, "The goals of magnetic fusion energy (MFE) research are to determine the optimum magnetic configuration(s) for attractive fusion energy production by using a spectrum of magnetic configurations ... (and to) be prepared to move forward with the next stage of MFE development ... (and to) provide fertile environment for new ideas and innovation in MFE." He said that "two over-arching themes have emerged from (the Working Group's) discussions." One is to develop "across magnetic concepts and across scientific disciplines" a "physics understanding and predictive capability to develop the scientific basis for fusion energy." The other is the "development and employment of plasma control tools" that will allow "scientific understanding, performance optimization, and innovative technological and scientific solutions." This will require a "partnership between technology and physics," he said.

Craig Olson (Sandia National Laboratories) gave the summary of the Inertial Fusion Concepts Working Group. He said, "Inertial Fusion Energy (IFE) offers an attractive path to fusion energy." He described an IFE power plant as "an integrated choice of target, driver, chamber and power conversion" systems. He noted that there are "five driver options being considered at this time," heavy ions, KrF lasers, diode-pumped solid state lasers, z-pinch, and light ions, and that each has "a choice of chamber options." He described the "issues" associated with all elements of the program. He also noted Magnetized Target Fusion (MTF) as having characteristics in common with both MFE and IFE. He said that "current research is leading to Integrated Research Facility(ies) in the next decade," so that choices will have to be made. A Roadmap was presented showing the major facilities on the way to a demonstration power plant.

Dan Barnes (Los Alamos National Laboratory) presented the summary of the Emerging Concepts Working Group. He said, "We endorse innovation at all levels and all aspects (physics, technology, new products, ...) of the national fusion program, including the recent Innovative Confinement Concepts (ICC) program and its contributions to the Spherical Torus (ST) and compact stellarator concepts." He said, "We believe there is a need for a continuous vigorous supply of genuinely alternative concepts, which will provide the program with exciting technical opportunities during the decades-long development of fusion." He said, "We define emerging concepts as qualitatively different approaches from mainline fusion that offer the potential for less expensive and/or more rapid fusion energy development." He described eleven concepts that were discussed in his group. He said, "Presently emerging concepts are about 5% of the (fusion) program and should be increased significantly."

Arnold Kritz (Lehigh University) gave the summary of the Plasma Science Working Group. He said that "common themes" among his subgroups were the "need for additional and improved comparisons between experiments, simulations and theory; need for advances in diagnostics and visualizations; utilization of tera-scale computers and modern computational techniques; and (making) connections to non-fusion applications." He said we should "devote a portion of the budget to enhance interaction with scientists working in related disciplines." He provided goals for several subtopics of plasma science.

Mohamed Abdou (UCLA) and Stan Milora (Oak Ridge National Laboratory) gave the summary for the Technology Working Group. Abdou said, "There are exciting opportunities for fusion technology research in the next decade," and he called for a "partnership with fusion plasma research." He said that such a partnership would result in "creating an improved vision for an attractive and competitive fusion product and a cost-effective path for fusion development." He described how various technologies would assist in this process through "performance enhancement, cost and complexity reduction." Milora said that improved technology would also "enable near-term progress on fusion devices," and described the opportunities in detail.

Farrokh Najmabadi (University of California at San Diego) presented the summary of the Energy Issues Working Group. He said, "To meet the projected growing demand of electricity and to stabilize carbon dioxide concentration in the atmosphere in 2050, a large number of new power plants are required." He said, "This represents an opportunity for fusion energy development," and urged that we "strive to gain broad acceptance of a plan to introduce commercial fusion energy by 2050 in order to be taken seriously by energy planners and forecasters." He said, "Tokamaks could lead to an attractive power plant. Stellarator, ST and IFE concepts could also lead to attractive power plants, but at this point, are behind in demonstrated performance. Emerging concepts may lead to improvements in power plant attractiveness but they should be evaluated mainly on the basis of physics credibility." He said, "It is too early to narrow down to one option and a balanced program is essential."

Grant Logan (Lawrence Livermore National Laboratory), who along with Mike Mauel and Rich Hawryluk (Princeton Plasma Physics Laboratory) was a co-organizer of the Summer Study, gave the closing remarks. In addition to thanking all who had contributed to the success of the gathering, he said, "The last two weeks has been an important step in the ongoing process of communication and integration of the MFE, IFE, plasma science and fusion technology communities in the Fusion Energy Sciences Program." He said, "For certain, this Summer Study has further refined and clarified the many issues and opportunities in the U.S. fusion program." He said, "One of the most important contributions of the Summer Study has been the cross-discipline interactions, not just in the cross-cutting and plenary sessions, but also, very importantly, in the many informal one-on-one and ad hoc group discussions, dinner discussions, and associated rump sessions." He said "We need to think of the Summer Study as a step in a continuing process of cross-community communication and integration."