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Research Semester and the Undergraduate Student Research Participation program involve students in nuclear physics projects. With the American Chemical Society, the DOE has developed an intensive summer school program that exposes students to research in nuclear power, waste disposal, nuclear nonproliferation, radiation safety, and nuclear medicine. Nuclear physics faculty members at undergraduate institutions often involve their students in nuclear research, especially at the user facilities, with NSF Research at Undergraduate Institutions (RUI) program support; about 9 percent of NSF-supported faculty are funded through the RUI program.

While these specific NSF and DOE programs provide opportunities for students who would otherwise not be able to participate in research, many more undergraduates are involved in nuclear physics research, directly supported by research grants. At a large number of universities, nuclear physics faculty involve undergraduates in their research projects, often as part of the research team, through senior theses and part-time or summer jobs. The synergism between research and teaching provides an early exposure to forefront research and state- of-the-art technology.

Earlier Education, Outreach, and Scientific Literacy

Given the rapid pace of technological advances, the future of the country and its economic welfare depend increasingly on the level of the technical and scientific sophistication of the population. The 1996 NSAC Long-Range Plan described the results of a survey on the involvement of nuclear physicists in undergraduate education, outreach, and scientific literacy. It is evident from the responses to the survey that many nuclear physicists are committing increasing amounts of their time and energy to these issues.

K-8 Education in Elementary and Middle Schools

Young children are fascinated by natural phenomena. Reinforcement of this fascination early in the educational process is a goal of many nuclear physicists. The broad variety of approaches includes programs for hands-on experience that have reached thousands of students; visiting minority professorships at research universities charged to interact with inner-city schools; and the Becoming Enthusiastic about Math and Science (BEAMS) program at TJNAF. The BEAMS program is a partnership with the local schools and the Commonwealth of Virginia; entire classes are brought to the facility for a full week of immersion in the scientific environment. To date, about 30,000 students have benefited from BEAMS and other programs at TJNAF.

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Contact with Teachers and Students in High Schools

Students often perceive science and mathematics as formidable and as unpopular with their peers. This situation can be improved only if one addresses both the perception of science by young people and the quality of their science education. Nuclear physics laboratories and universities organize many programs for high school students and their teachers. Some of these efforts have been supported by federal funds or by the local institution, but many rely on the voluntary work of individual scientists. Examples include Saturday classes for in-service teachers; multiweek summer programs for students, sometimes involving teachers as well; lectures and demonstrations in schools, coupled with development of instructional material; and extension of computer facilities to high schools, so that students and teachers can access the Internet and the many innovative activities available there.

Activities Addressing Underrepresentation of Women and Minorities

It is unfortunate that large segments of our society are underrepresented in science and technology. The nuclear physics community has endeavored to encourage women and minority students to pursue careers in physics through individual volunteer efforts and specific programs supported by DOE and NSF. Many universities, colleges, and national laboratories bring female and minority students in middle schools for one day or longer visits to participate in hands-on science (especially physics) and to meet practicing scientists. Nuclear scientists have been active in such programs as the American Physical Society’s Women in Physics project.

National and university laboratories have also committed resources to recruit students from historically black colleges and universities (HBCUs) and hispanicserving institutions (HSIs) to participate in the laboratories’ summer science research programs. These programs sometimes include support for HBCU faculty participation. For example, TJNAF’s efforts have contributed to a significant growth in faculty hirings in HBCUs and HSIs. As a result, Hampton University has developed a new Ph.D. program and graduated about 20 undergraduates, all African American, one-third of whom has done research in nuclear physics. Mentoring programs for promising minority undergraduates have been instituted by national laboratories and universities.

It appears that the programs described above have had positive effects on an overall societal problem, but the issues remain.

OUTLOOK

The past direct contributions of nuclear physicists to problems facing the nation are substantial. This is surprising, given the direction of research in

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Nuclear Physics: The Core of Matter, The Fuel of Stars

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nuclear physics, which involves the most fundamental aspects of nature and is not directly focused on societal issues. If one examines the contributions outlined above, three threads running through them can explain this result. First, the techniques of nuclear physics are relevant to many of our national problems. Second, the broad training and team experience of many students in nuclear physics provide the background that allows them to confidently and fruitfully apply nuclear techniques in many settings. And third, the varied properties of nuclei, and their radiations, lend themselves to the remarkably broad range of specific applications discussed in this chapter.

It is appropriate to ask whether these contributions are likely to continue. The impact of basic research is hard to predict, but it can lead to profound and revolutionary developments, the case of nuclear fission being an outstanding example. Many of the items discussed above seem likely to have still greater importance in the future, and new applications will certainly arise from new technical developments in nuclear physics. One can anticipate continued growth in the role of nuclear physics in generating applications that contribute to society.

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Nuclear Physics: The Core of Matter, The Fuel of Stars

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Appendix

Accelerator Facilities for Nuclear Physics in the United States

Tables A.1 and A.2 summarize nuclear physics accelerator facilities currently in operation or under construction in the United States. In addition to the accelerator parameters and performance characteristics, the tables list the primary areas of research that each one addresses. Figure A.1 gives an overview of facilities and their geographical location.

The major new facilities of the nation’s nuclear physics program are the Continuous Electron Beam Accelerator Facility (CEBAF) at the Thomas Jefferson National Accelerator Facility, which recently came into operation, and the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory, which is scheduled to begin operation in 1999. CEBAF (shown in Figure 7.1) is a superconducting, recirculating linac designed to deliver continuous electron beams of up to 200 A of current, polarized and unpolarized, simultaneously to three experimental areas. The design energy is 4 GeV, but operational experience with the superconducting cavities indicates that an energy of up to 6 GeV will be possible.

Nearing completion, RHIC (shown in Figure A.2) is the first colliding-beam facility specifically designed to accommodate the requirements of heavy-ion physics at relativistic energies. RHIC will provide heavy-ion collisions for a range of ion species up to gold, with beam energies of 30 to 100 GeV/nucleon for each of the colliding beams.

In addition to these two large nuclear physics facilities, six medium-size user facilities supported by DOE and NSF address different key aspects of nuclear physics, indicated in Figure A.2.

The Bates Linear Accelerator Center at MIT provides high-quality electron

197

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beams up to an energy of 1 GeV. The pulsed linac and the isochronous recirculator provide currents in excess of 80 A at a duty-factor of up to 1 percent. The existing accelerator-recirculator system feeds the recently completed South Hall Ring, which will provide close to 100 percent-duty-factor beams. The 190 m-circumference ring will operate in the energy range up to 1 GeV at peak circulating currents of up to 80 mA, and extracted currents will be up to 50 A.

Three superconducting cyclotrons have been built at the National Superconducting Cyclotron Laboratory of Michigan State University (MSU/NSCL). Two

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of these, the K500 and the K1200, are currently being coupled in a program to upgrade the capabilities of the MSU system. The K500, the world’s first superconducting cyclotron, operated from 1982 to 1988 in support of the nuclear physics program at MSU. The K1200 is the world’s highest-energy (~10 GeV) continuous-wave (CW) cyclotron and has been used in support of the nuclear physics program since 1988. Both the K500 and the K1200 operate at 5 T. The upgraded facility will provide intense, high-energy beams of heavy ions for inflight fragmentation to produce intense secondary radioactive beams.

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The Indiana University Cyclotron Facility is active in areas of beam-cooling technologies and polarized proton beams. Two cyclotrons provide protons with energies up to 200 MeV for direct beams, as well as serving as the injector complex for the Cooler Ring. This ring can accelerate protons to an energy of 500 MeV. In addition, the Cooler Ring has a state-of-the-art electron-cooling system capable of providing high-resolution, very dense beams. A new synchrotron injector into the Cooler was recently completed, providing a two-orders-of- magnitude increase in beam intensity. Distinguishing characteristics of the facility include polarized beams in all machines and internal polarized gas-jet targets in the cooler.

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ATLAS at Argonne National Laboratory consists of a superconducting linear accelerator, which is injected by either a 9-MV tandem Van de Graaff or a new positive-ion injector (PII) consisting of two ECR ion sources and a superconducting injector linac of novel design. Using the PII, ATLAS routinely accelerates intense beams up to uranium with energies above the Coulomb barriers and with excellent beam properties. The accelerator has a 100 percent duty cycle, can provide very short beam pulses (<150 psec), and is ideal for highresolution heavy-ion nuclear physics research where nuclear structure effects are particularly important.

The Holifield Radioactive Ion Beam Facility (HRIBF) was recently brought

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FIGURE A.1 Illustration and geographical distribution of nuclear physics laboratories in the United States. Shown are major national user facilities, as well as the smaller, dedicat-

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ed university laboratories that, together and in a synergistic relationship, cover the broad range of science that is described.

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