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Scientists the world over eagerly await the availability of intense beams of exotic, short-lived nuclei to open new research areas in physics, from fundamental studies of nuclear structure to the processes that occur in supernovae. A new technology demonstrated at Argonne's heavy-ion accelerator promises to make such beams available.
The technology, demonstrated by a team led by physicist Guy Savard, provides a new way to generate intense beams of short-lived, radioactive exotic nuclear isotopes -- atoms whose nuclei have the same number of protons but differing numbers of neutrons -- for basic research in nuclear physics and other sciences. Argonne hopes to use the new technique in its Advanced Exotic Beam Facility, an initiative now under development.
The Advanced Exotic Beam Facility will be a unique complex of accelerators and instruments to study the properties and interactions of "exotic" nuclei -- short-lived nuclei that do not occur naturally on earth but are key to the production of the elements in stars. Physicists would produce, then rapidly extract and separate these nuclei before delivering them to Argonne's superconducting heavy-ion accelerator, the Argonne Tandem Linac Accelerator System (ATLAS).
But before sensitive instruments can begin recording the data that may lead to physics breakthroughs, specific ions must be produced, separated and accelerated in large numbers. In first-generation exotic beam facilities currently in operation around the world two different approaches are used.
Through thick …
One established method of making beams of unstable ions is "isotope separation on line," or ISOL. A driver beam directly irradiates a thick, heated target of metal foil or compressed powder. The nuclei in the driver beam react with nuclei in the target, forming radioactive isotopes. These reaction products come to a stop in the thick target. At the elevated temperature of the target material, the atoms migrate out and are funneled into an ion source, where they are ionized and reaccelerated. The accelerated beams are of low energy with high quality.
This traditional ISOL method, however, is so slow that many of the unstable atoms decay before they can be accelerated. Yet these fast-decaying particles are just the ones scientists want most for their experiments. Furthermore, the standard ISOL method cannot be used with about two-thirds of the known elements because their melting points are too high or they are too chemically reactive.
… and thin
Alternatively, beams of short-lived nuclei are produced by using a thin target to break high-energy beams of stable heavy ions into fragments. The fragments are separated "in-flight," essentially instantaneously, for research without being stopped and re-accelerated.
This method is currently in use at several nuclear physics laboratories, yielding beams with higher energies but greater energy variation and divergence than beams from ISOL-based facilities. To date the two methods have been considered complementary.
Best of both worlds
The new method, demonstrated recently at ATLAS, magnetically separates energetic exotic ions produced in thin targets and brings them to rest in a "catcher cell" filled with pressurized helium. Normally, these ions, which are positively charged, would neutralize themselves by capturing electrons from surrounding atoms. But helium electrons are the most tightly bound of any element, so the stopped ions remain positively charged.
Savard and his co-workers demonstrated that a combination of radio frequency and static electric fields inside the gas cell can efficiently extract the stopped ions in a few thousandths of a second.
The whole process, from target to gas cell to ATLAS, occurs in a matter of milliseconds. This new separation technology, in combination with ATLAS and a powerful new driver accelerator, will give physicists high-quality exotic beams of any element in the periodic table.
Researchers from Argonne and Michigan State University (MSU) are working to combine a magnetic fragment separator with the fast gas catcher.
The new, fast gas catcher technology, combined with the techniques developed at fragmentation-type facilities, has led to the new model for exotic beam facilities: the "projectile fragmentation-based ISOL facility."
Liquid target
To gain full benefit from the high-power, heavy-ion driver beam also requires a breakthrough in target technology. Engineers from Argonne's Technology Development and Energy Technology Divisions are helping develop a new target, which uses a miniature version of a proposed method for removing heat from a fusion reactor. The primary ion beam will shine on a thin stream of liquid lithium, which flows in a closed loop through a heat exchanger to dissipate the high beam power. Otherwise the intense beam would destroy the target.
"The fragmentation-ISOL technology is a collaboration of several Argonne divisions with important contributions from MSU and additional input from European and Japanese scientists," said Jerry Nolen, director of the ATLAS Facility.
More projects are under way to iron out this new approach. Further development of the gas catcher will be carried out at ATLAS. Prototype components of the high-power, superconducting driver linear accelerator will be built and evaluated, and engineering designs of the liquid-lithium target will be tested.
"This method looks like a winner and it's getting a lot of attention," Nolen said, "but there's still a lot of work left to do."
John Sackett, deputy associate laboratory director for Argonne-West, and Engineering Division Director Leon Walters are the general and technical program chairs for Global '99, the world's premier international conference on future nuclear systems.
The Fuel Cycle and Waste Management Division of the American Nuclear Society and the Idaho section of the American Nuclear Society are co-sponsoring the conference.
Scientists, educators, and government officials from many nations will descend on Jackson Hole, Wyo., Aug. 29 -Sept. 3 to discuss and debate the worldwide future of nuclear energy.
Global '99 will focus on fuel cycle, waste management, and advanced reactor concepts. The conference will also include discussions of non-power related nuclear technology and human and facilities resources.
The Global conferences have grown quickly. The first in the series, Global '93, had about 200 technical papers. Global '99 expects more than 400 technical papers, with nearly half of the papers coming from outside the United States. More than 20 organizations from around the world are acting as co-sponsors.
Conference registration includes a welcome reception, buffet dinner and lunch coinciding with the poster sessions, and a Western banquet at the Bar-J Ranch. A reception will be held at the National Wildlife Art Museum; Idaho Governor Dirk Kempthorne and Wyoming Governor Jim Geringer have been invited.
For a conference schedule and registration information, call Todd Allen at (208) 533-7760 or todd.allen@ anlw.anl.gov. or access the Global `99 Web page at http://www.anlw.anl.gov/global99/.
Volunteers are needed to help out at Argonne-East's annual employee picnic, Saturday, July 10, from 10 a.m. to 3 p.m. at Argonne Park. To volunteer, call Stan Reinke (ECT) at ext. 2-6957.
This year's picnic will feature more activities and rides for adults, who can look forward to climbing a 30-foot wall, spinning in the Orbitron, getting stuck in the Velcro obstacle course, playing bingo, "Beaning Babies" and walking the pie walk.
Other attractions include a live band, face painters, clowns and a variety of food and beverages available for purchase.
Argonne, DOE and University of Chicago employees and their families are invited to the annual get-together sponsored by the Argonne Club and the Argonne Credit Union. Admission is free.
Ten Argonne employees will receive the highest honor the University of Chicago can award to laboratory employees.
The University of Chicago Distinguished Performance Awards and Outstanding Service Awards will be bestowed at a ceremony at 3 p.m. on Thursday, July 15, at Argonne-East's Building 213 Cafeteria. All employees are invited to attend the ceremony and help honor the recipients.
The Distinguished Performance Awards recognize achievements or leadership by employees engaged in scientific and technical activities. Awardees will receive a certificate, a medal and a check for $3,000. Awardees are Esen Ercan Alp and Deming Shu (both XFD), Michael R. Norman and Juan Carlos Campuzano (both MSD), L. Walter Deitrich (ERA) and Samit K. Bhattacharyya (TD).
Outstanding Service Awards are the highest honor the university gives to Argonne employees in support positions. Winners receive an engraved plaque and a check for $3,000. Recipients are Benny E. Clifft (PHY), Midge A. Urban (ES), Anthony W. Uzzardo (IPD-MED), and Gordon L. Veerman (ESH-FD).
For the second year, Argonne-East has hosted interns for a two-week orientation on nuclear nonproliferation and export control.
Six graduate students were selected to participate in the Nonproliferation Graduate Program (NGP), coordinated by Argonne's Division of Educational Programs and Technology Development Division for the Department of Energy's Nuclear Transfer and Supplier Policy Division.
The program trains future leaders in nonproliferation while helping to establish or enhance nuclear export control systems in the former Soviet Union. The interns will support ongoing DOE/NIS export control cooperation projects.
During their orientation, the interns received briefings on technical aspects of nuclear nonproliferation and export controls. Following their orientation, the interns spend several weeks in Washington D.C. and at U.S. national laboratories continuing their policy and technical training.
Three NGP interns will go to Russia, Kazakhstan and Ukraine this September, while the others will begin their foreign practicum in September 2000.
The program has a special appeal to each intern. "I think it's a very good chance to get some actual experience implementing a policy in a foreign country," said John Van Sickle, an NGP intern.
Interns were selected based on their fluency in Russian, interest in nuclear nonproliferation activities and related study and work experiences.
For more information about the program, contact Diana Naples (TD) at ext. 2-1239 or visit www.dep.anl.gov/NGP/ on the World Wide Web.
Hazardous chemicals are essential to much of the work at Argonne, and taking a few extra precautions can prevent accidents and incidents.
"The first thing people should do before working with an unfamiliar chemical is read the material and safety data sheet (MSDS) that accompanies each chemical," said Chemical Hygiene Officer Aubrey Smith (ET).
Other precautions and good practices include:
* Minimize and control exposure by using protective clothing and equipment when handling hazardous chemicals -- even small amounts.
* Dispose of all chemicals through Waste Management at ext. 2-5866, never down the drain.
Industrial Hygienist John Davis (ESH) provided more helpful reminders:
* If possible, substitute a safer chemical for a hazardous one.
* If you are suspicious about a chemical or air quality, call Industrial Hygiene at ext. 2-3310. They can monitor conditions and suggest controls.
* New standards are in effect for more workplace monitoring of asbestos, lead, cadmium, methylene chloride and beryllium. When working with these materials, call Industrial Hygiene as part of the Integrated Safety Management System (ISMS).
Former Director of the Reactor Engineering Division Bernard Israel Spinrad, 74, died March 1 at his home in Seattle, Wash.
Spinrad came to Argonne in 1949, starting out as a physicist in the Theoretical Physics Division. He helped design the Savanna River reactor and trained staff to operate it. He became director of the Reactor Engineering Division in 1957.
In 1967, he was recruited by the International Atomic Energy Agency to serve as director of the division of nuclear power and reactors.
He returned to Argonne in 1970 where he worked as a senior physicist in the Applied Physics Division until 1972.
He was a fellow of the American Physics Society and former director of the American Nuclear Society. In 1956, he was named "Man of the Year" by the Chicago Chamber of Commerce.
He is survived by his former wife Marion; his children, Alexander, Diana, Mark and Jeremy; and his wife Lois.
Robert J. Zimmer, deputy provost for research at the University of Chicago, has been appointed to the university's board of governors for Argonne.
The board of governors provides guidance, oversight and direction to Argonne management. The board's 21 members are drawn from University of Chicago trustees, officials and faculty, representatives from other universities and industry leaders.
Zimmer is Max Mason Distinguished Service Professor of Mathematics at the university. He has served as the university's associate provost for research and education, chairman of the Department of Mathematics and professor of mathematics.
Zimmer is a member of the Illinois Science and Technology Advisory Committee, the Illinois Coalition Science Priority Committee and is on the board of directors of ARCH Development Corporation, which licenses Argonne-developed intellectual property. He has also been a member of the Council of the American Mathematical Society and the American Mathematical Society's committee on federal policy agenda.
He has written two books and more than 80 research articles.
Valerie Gaines (IPD), Mary Ann Hejny, CPS (RA), Elaine London, CPS (ESH), and Diane Hawk, CPS (BIO) have been named president, vice-president, secretary, and tresurer, respectively, of Argonne's chapter of the International Association of Administrative Professionals (IAAP) for the 1999-2000 season.
Monthly chapter meeting are held the third Wednesdays of every month. All administrative office personnel are invited to attend.
Starting July 1, a lower monthly rate for employer-provided group term life insurance over $50,000 will take effect.
Taxable income for group term life insurance carriers will be reduced, lowering social security and Medicare withholdings - resulting in greater net pay.
Employees are not taxed on the value of the first $50,000 of group term life insurance provided by Argonne. The value of the remaining coverage over $50,000 is added into the employee's gross income using a rate table based on age.
Prior to July 1, the taxable value of the insurance was determined based on 10 age brackets, with rates ranging from $0.08 to $3.76 per $1000 of coverage.
The new table lowers the rates for all age groups and divides the "under 30" group into two groups: "under 25" and "25-29." The new rates, based on 11 age brackets, range from $0.05 to $2.06 per $1000 of coverage over $50,000.
The Argonne mentoring program is looking for employees who want to share skills with others, and those who want to learn from someone who can help them develop their abilities.
Argonne's Mentoring Program can help employees maximize their personal development and their contributions to the laboratory. Participants take part in a structured, facilitated mentoring relationship which offers assistance in setting individual career goals and enhancing skills and capabilities.
Participation will be based on availability of appropriate mentor-mentee matches. All Argonne employees are eligible.
For an application, call the Diversity Program Office at ext. 2-3022 (Argonne-East) or ext. 3-7144 (Argonne-West).
Three courses will be offered by Human Resources-Performance Development during the month of July. To enroll, contact a Training Management System representative.
* Presentation Excellence (HR532) -- Improve presentation delivery to look, sound and feel confident, organized and effective. The class will be held on Wednesday and Thursday, July 21-22 from 8:30 a.m. - 5 p.m. in Building 212, Room A157.
* Introduction to Team Building For New Supervisors (HR631) -- Learn strategies for one-on-one and team relationships. The class will be held on July 28 from 8:30 a.m. _ 3:30 p.m. in Building 201, Room 274.
* Preventing Sexual Harassment for Supervisors (HR140) -- Addresses the role of a supervisor and the responsibilities in addressing sexual harassment in the workplace. Learn to recognize inappropriate behavior. The class will be held on July 23, from 9 a.m. - 10:30 a.m. in Building 201, Room 190.
For complete class descriptions, go to http://www.hr.anl.gov and follow the links for HR Departments and Performance Development.
