Opportunities in Nuclear Science

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Opportunities in Nuclear Science OPPORTUNITIES IN NUCLEAR SCIENCE A Long-Range Plan for the Next Decade April 2002 The DOE/NSF Nuclear Science Advisory Committee U.S. Department of Energy • Office of Science • Division of Nuclear Physics National Science Foundation • Division of Physics • Nuclear Science Section This document was produced by the Berkeley Lab Technical and Electronic Information Department in collaboration with the Nuclear Science Advisory Committee. TEID JO#5547 This document was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, nor any of their contractors, subcontractors or their employees makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or any third party's use or the results of such use of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof or its contractors or subcontractors. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof. OPPORTUNITIES IN NUCLEAR SCIENCE A Long-Range Plan for the Next Decade April 2002 The DOE/NSF Nuclear Science Advisory Committee U.S. Department of Energy • Office of Science • Division of Nuclear Physics National Science Foundation • Division of Physics • Nuclear Science Section The Nuclear Science Advisory Committee James Symons (Chair) Lawrence Berkeley National Laboratory Ricardo Alarcon Arizona State University Betsy Beise University of Maryland Tom Bowles Los Alamos National Laboratory Wit Busza Massachusetts Institute of Technology Jolie Cizewski Rutgers University Kees de Jager Jefferson Laboratory Alejandro Garcia University of Notre Dame Robert Janssens Argonne National Laboratory Krishna Kumar University of Massachusetts, Amherst Walter Loveland Oregon State University Larry McLerran Brookhaven National Laboratory Alice Mignerey University of Maryland Joel Moss Los Alamos National Laboratory Witold Nazarewicz University of Tennessee/Oak Ridge National Laboratory Shelley Page University of Manitoba Vijay Pandharipande University of Illinois Mark Riley Florida State University Richard Seto University of California, Riverside Brad Sherrill Michigan State University Edward Shuryak Stony Brook University Contents Executive Summary . 1 1. Overview and Recommendations . 3 2. The Science . 13 Protons and Neutrons: Structure and Interactions . 14 Atomic Nuclei: Structure and Stability . 28 QCD at High Energy Densities: Exploring the Nature of Hot Nuclear Matter . 43 Nuclear Astrophysics: The Origin of the Elements and the Evolution of Matter . 55 In Search of the New Standard Model . 70 3. Facilities for Nuclear Science . 85 4. The Nuclear Science Enterprise . 97 Education and Outreach . 98 Interdisciplinary Aspects . 107 International Collaborations and Cooperation . 111 Impact and Applications . 113 5. Looking to the Future . 121 6. Resources: Funding the 2002 Long-Range Plan . 137 Appendix . 142 Glossary of Facilities and Institutions . inside back cover Preface The DOE/NSF Nuclear Science Advisory Committee of the Department of Energy and the National Science Foundation is charged with providing advice on a continuing basis regarding the management of the national basic nuclear science research program. In July 2000, the Committee was asked to study the opportunities and priorities for U.S. nuclear physics research, and to develop a long-range plan that will serve as a frame- work for the coordinated advancement of the field for the next decade. The plan contained here is the fifth that has been pre- pared since the Committee was established. Each of the earlier plans has had substantial impact on new directions and initiatives in the field. NSAC is indebted to the Division of Nuclear Physics of the American Physical Society for organizing a series of four topical Town Meetings in late 2000 and early 2001. These meetings provided a forum for community input into the planning process and resulted in the production of White Papers that provide the scientific underpinning of this plan. A fifth White Paper on Education, covering the breadth of the field, was also written during this time. A Long-Range Plan Working Group (see Appendix) including the Committee members and additional representa- tives from the nuclear science community was formed to determine overall priorities for the field. The working group met in Santa Fe, NM during the week of March 25 , 2001. During this meeting, the scientific opportunities and priorities were discussed in depth and consensus was reached on the prioritized recommendations contained in this report. This report was prepared by the members of the Long- Range Plan Working Group. However, many others, too numerous to mention individually, contributed to the final document either as authors or readers. The chairman wishes to thank Douglas Vaughan, our technical editor, for his tireless efforts to create a coherent document. The Committee is indebted to all the members of our com- munity for their support of the planning process. Executive Summary Nuclear science is a key component of the nation’s This Plan has emerged from a process in which more research portfolio, providing fundamental insights into the than a thousand members of the nuclear science community nature of matter and nurturing applications critical to the participated by attending a series of public “town meet- nation’s health, security, and economic vitality. It is a field ings,” which led to the preparation of topical white papers. with tremendous breadth that has direct relevance to under- A smaller working group then prioritized the resulting rec- standing the evolution of matter in the universe. Nuclear ommendations. This Plan addresses the charge to NSAC to scientists today use sophisticated experimental and theoreti- develop a “framework for the coordinated advancement of cal tools to probe the properties of nuclei and nuclear matter the field.” The opportunities for such advancement are and of their ultimate constituents—quarks and gluons. At extraordinary, and addressing them will ensure the continu- the same time, nuclear science is probing key interdiscipli- ing vigor of nuclear science. The Plan includes the follow- nary questions: the basis of fundamental symmetries in ing four recommendations, which address critical funding nature, how matter emerged in the first moments of the uni- issues facing the present program and guide new invest- verse, the nature of supernovae, and the origin of elements ments for the future: in the cosmos. Nuclear science continues to have significant 1. Recent investments by the United States in new and impact on other fields. The field is also a prolific source of upgraded facilities have positioned the nation to con- today’s technological work force. More than half of nuclear tinue its world leadership role in nuclear science. The science Ph.D.’s apply their training outside their field— highest priority of the nuclear science community is to notably, in medicine, industry, and national defense. exploit the extraordinary opportunities for scientific The long-range plan for nuclear science that follows discoveries made possible by these investments. includes descriptions of recent progress across the full Increased funding for research and facility operations range of the field. One discovery, however, merits partic- is essential to realize these opportunities. ular attention. Remarkable new measurements show that Specifically, it is imperative to neutrinos produced by the nuclear reactions that power • Increase support for facility operations—especially the sun change their character on their 93-million-mile our unique new facilities, RHIC, CEBAF, and journey from the solar core to the Earth. This result is a NSCL—which will greatly enhance the impact of critical vindication of the theory of energy production in the nation’s nuclear science program. the sun: We now understand quantitatively what makes the sun shine. The transformation of neutrinos requires • Increase investment in university research and that they have mass, generating new questions at the same infrastructure, which will both enhance scientific time old ones are resolved. The Standard Model of ele- output and educate additional young scientists mentary particles provides no mechanism for neutrino vital to meeting national needs. mass and thus must be modified. In addition, theories of • Significantly increase funding for nuclear theory, the evolution of the universe and the nature of the missing which is essential for developing the full potential dark matter must take these discoveries into account. of the scientific program. EXECUTIVE SUMMARY 2. The Rare Isotope Accelerator (RIA) is our highest pri- 4. We strongly recommend the upgrade of CEBAF at ority for major new construction. RIA will be the Jefferson Laboratory to 12 GeV as soon as possible. world-leading facility for research in nuclear structure The 12-GeV upgrade of the unique CEBAF facility and nuclear astrophysics. is critical for our continued leadership in the experi- The exciting new scientific opportunities
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