Some of this week's stories

`AYE-Ball' gives physicists a glimpse
over the edge of nuclear stability

"We were making isotopes so unusual, nothing is known about them," said Kim Lister (PHY). "We know pretty well what's happening in stable nuclei. The question is, how do these models hold up on the edge of stability?"

AYE-Ball -- the first three letters stand for Argonne, Yale (University) and European -- has been dismantled, but its success paved the way for Argonne to receive Gammasphere, an instrument many times more powerful.

AYE-ball was a roughly spherical instrument comprising 20 gamma-ray detectors from several institutions. Each detector contained a germanium crystal ingot about the size of a coffee cup, cooled with liquid nitrogen.

The new nuclei were made by aiming a beam of ions (atoms stripped of one or more electrons) from the Argonne Tandem Linear Accelerator (ATLAS) with an extremely thin foil target.

In a typical experimental run, one in a million of the ATLAS-beam ions collided with an atom in the foil and fused with its nucleus, creating a new, more massive nucleus. As the nucleus settled down from its highly excited state, AYE-Ball detected flashes of gamma rays (light of extremely high energy).

Recoiling from the collision, the nucleus entered another detector called the Fragment Mass Analyzer (FMA). The FMA separated the nucleus of interest from the thousands of less interesting collision products and recorded its mass. The device was designed by Cary Davids (PHY).

The nucleus then embedded itself in a third detector, sensitive to alpha-particle emissions. Unstable nuclei attempt to stabilize themselves by emitting particles like protons (hydrogen nuclei) or alpha particles (helium nuclei).

The time a nucleus takes to emit a particle and the energy of that particle are "unique fingerprints," Davids said, revealing the difference between nuclei having the same total number of protons and neutrons, but in different amounts of each. For example, this type of decay can discriminate between a nucleus of gold-171, with 79 protons and 92 neutrons, and platinum-171, with 78 protons and 93 neutrons.

By tying together signals from AYE-Ball, the FMA and the particle detector, physicists could deduce the mass of the nucleus, its atomic number and something about the forces responsible for its stability -- measurements never before conducted with these highly unstable isotopes.

A major challenge during the four-month series of experiments was the enormous time-scale difference between the three phases of the operation. The gamma flash lasts about a trillionth of a second; the flight of the new nucleus through the FMA takes about a millionth of a second, and the particle decay may occur several seconds later.

The nuclei under study are produced in small quantities, along with large numbers of less interesting products. "It's like searching for smaller and smaller needles in larger and larger haystacks," Davids said.

Another challenge was assembling the AYE-Ball itself from components of different sizes and shapes on loan from many institutions. Planning and assembly took four months.

Gammasphere

Although AYE-Ball offered a glimpse over the edge of nuclear stability, the new "Gammasphere" detector will give physicists the equivalent of a pair of binoculars. Now at Lawrence Berkeley National Laboratory, the Gammasphere is the world's most sensitive instrument for detecting gamma rays, with 110 high-resolution detectors. It will be moved to Argonne in 1997, to be used with the FMA.

A hundred times more sensitive than AYE-Ball, Gammasphere contains high-resolution germanium crystal detectors and bismuth-germanate scintillation counters.

AYE-Ball gave Argonne physicists a "tantalizing look" at what will be possible when the Gammasphere is coupled to the Fragment Mass Analyzer.

Junior Wells to play
at Blues Fest VI

Tickets are $10, and are available by phone at ext. 2-4004. Tickets will be sold in the Building 213 cafeteria at lunchtime the weeks of March 11-16 and March 25-29.

Marriott will provide wine, soft drinks and snacks for purchase the night of the performance.

Movie execs: Choice of Argonne
helped write the film's script

"Chain Reaction" (The title was changed from "Dead Drop" the day of the seminar) started out as an cloak-and-dagger espionage movie, said location manager Mike Malone, who spoke with publicist Deborah Simmrin. But director Andrew Davis changed the content of the movie after touring the Argonne site, which he chose from among several places suggested by the Illinois Film Commission. The film will now emphasize technology.

"We knew it was going to be a scientific movie," Malone said. "It really was the location writing the script. Davis' interest is in the future, and the uses of technology."

Changes are substantial, Malone said, and "the ending is being re-written even as we speak."

The script calls for about 27 extras, Malone said. The call for extras in a recent edition of Argonne News brought more than 250 photos, which were forwarded to the film's casting office in Chicago. Several employees were called on the first day of shooting, Feb. 12, and more will be needed when film crews return in April.

Scenes being shot at Argonne will appear near the end of "Chain Reaction," Malone said, as the real laboratory doubles for the mysterious "Mount Weather," a clandestine research facility. Crews spent a day filming at Eastgate, then moved indoors to the Zero-Gradient Synchrotron tunnel and Continuous Wave Deuterium Demonstrator. The best time for employees to observe filming will be in April, when crews will shoot outdoor scenes.

"The film will be Fox's major summer presentation for this year," Malone said, with a budget in excess of $50 million.

An autograph session with the movie's actors, which include Keanu Reeves and Morgan Freeman, is possible, Malone said, nobody should be holding their breath. "It's up to the actors, and depends on how our days are going. We work 12- to 16-hour days."

Coins to commemorate
Argonne's 50th anniversary

The anniversary medallion is one ounce of .9999 silver, with the 50th anniversary logo on one side and the Argonne logo on the obverse. The coin comes in a green velvet presentation box. Only 7,500 coins will be minted.

Coins cost $27. Argonne employees, families and retirees, DOE employees and contractors get first chance to order the medallion. After March 30, unsold medallions will be offered to the public.

The 50th anniversary coin will be on display from Feb. 19-23 and March 4-8 at the Building 213 cafeteria from 11:30 a.m. to 1 p.m. Orders can be taken at the display; coins will be delivered six to eight weeks after ordering.

Agreement to bring
Lake Michigan water

The water commission will begin construction this spring on a pipeline to connect Argonne to the commission's water supply system.

In addition to improving the quality of life for coffee drinkers, the new pipeline will eliminate an environmental compliance issue. The laboratory occasionally violates Illinois Environmental Protection Agency standards for "total dissolved solids" in water discharged into Sawmill Creek. These solids result mainly from the high levels of dissolved solids in the laboratory's current well water supply.

Most of the compliance problems should be solved by the use of Lake Michigan water. The remainder should disappear when upgrades to the water treatment plants, now underway, are completed.

Phone costs to decrease
as ECT restructures rates

These steps are the first of a laboratory-wide initiative to associate telecommunication costs with those who use and benefit from the services provided. Previously, many costs were incorporated into telephone base station rates.

Changes include:

* The telephone base station rate will be reduced from $40 per month to $37.

* Using a pager will cost $3 a month; radio access will cost $10 a month.

* The cost of a dedicated circuit will rise from $4 per termination to $6 per termination.

* Invoices that require special handling will incur a 10 percent charge.

Unused or seldom used phones, pagers and radios can be returned to ECT to reduce costs. For assistance, call ext. 2-2730. For more information on ECT's telecommunications services, visit the division's World Wide Web page at http://www.anl.gov/ECT/telecom/anltele.html.

Employees invited to cheer
High School Science Bowl teams

Sixteen teams will compete in a double-elimination tournament. Tams will compete in oral question-and-answer rounds in which one four-student team will attempt to outscore another team. The students will answer questions from the fields of astronomy, biology, chemistry, earth science, physics, algebra, geometry, trigonometry, calculus, computer science and general and applied science.

The winning team receives an expense-paid trip to Washington, D.C., to compete in the Department of Energy's National Science Bowl.

The Argonne Science Bowl is funded by the Argonne Department of Educational Programs.

Lab's new home page debuts ...

The new home page features blue and gold versions of Argonne's 50th anniversary logo with "hot buttons" and other art in matching colors. The art was designed by the same IPD-MED contractor who recently designed a home page for rock star Elton John.

The array of new hot buttons includes:

* "Argonne History" provides hypertext links to a timeline, feature articles and news releases on Argonne's history.

* "Argonne's 50th Anniversary" provides a schedule of the many events that are part of the laboratory's 50th anniversary celebration.

* "Gee Whiz" is a menu of Argonne activities that have general public interest. Current items are MCS's virtual environment CAVE, DEP's Newton "Ask-a-Scientist" bulletin board, and a Rube Goldberg machine contest sponsored by DEP and OPA.

... and latest version of Netscape
available on public volumes

Argonne's contract with Netscape allows previous Netscape purchasers to install this version and any other major or minor versions released through Dec. 31. Passwords used to extract the files downloaded from the public volumes are the same as previous versions.

PC users can get access to public volume a variety of ways -- the easiest being via a World Wide Web browser. Point the browser to http://www.anl.gov/ECT/Local-ANL/pcpublic.html. Other PC access methods are also indicated on this Web page.

Macintosh users can connect to the Mac Public Volume through Appletalk. Unix users can connect to their platform-specific versions of Netscape 2.0 on the Andrew File System (AFS) after getting access permissions from Linda Clark at ext. 2-8403.

To obtain a new Netscape license, contact Clark.

Controllers class
to be held on-site

Programmable logic controllers (PLCs) use electronics and solid state circuitry to control various kinds of machinery, replacing electromechanical relays, counters and timers.

"Introduction to Programmable Controllers" will be held on Wednesdays in Building 202, Room B169, from 4:30 p.m. to 8:30 p.m. This class will feature use of computer simulations of PLC controls. Class size is limited.

Prerequisites are "Schematic Interpretation" (COD 111) or instructor approval. Contact Karen Kroczek at ext. 2-8764 by March 4 for more information or to request an educational support form.

"Materials Chemistry at Argonne," a seminar by Dieter Gruen (CHM) will be held Monday, April 8, not March 4 as indicated on the Argonne 50th anniversary calendar.

Monday, Feb. 19

Argonne Risk Seminar Series: "CRESP--Past, Present and Prospects" by Charles W. Powers, Executive Director, Consortium for Risk Evaluation with Stakeholder Participation. 10 a.m., Bldg. 900, Conference Room A04.

Energy Technology Division Seminar: "Recent Developments in Energy Technology Division's Time-of-Flight Chemical Sensors" by Stephen L. Dieckman, (ET). 10:30 a.m., Bldg. 212, Conference Room A157.

Chemistry Division Monday Morning Seminar Series: "Biomimetic TiO2 Photocatalysis - A Model System for Photosynthesis" by Tijana Rajh, (CHM). 11 a.m., Bldg. 200 Auditorium.

Materials Science Division Informal Seminar: "Structural Evolution in Epitaxial GaN Films Grown on c-Plane Sapphire by Atmospheric Pressure MOCVD" by James S. Speck, Materials Department University of California, Santa Barbara. 2 p.m., Bldg. 212, Conference Room A157.

High Energy Physics Division Theoretical Physics Seminar: "Photon Plus Charm Production at Colliders in Next-to-Leading Order QCD" by Lionel Gordon, (HEP). 2 p.m., Bldg. 362, Conference Room E188.

Tuesday, Feb. 20

ANL Petroleum Seminar Series: "Petroleum Composition and Its Influence on Refining" by James Speight, Western Research Institute, Laramie, Wyo. 10:30 a.m., Bldg. 212, Conference Room A157.

Physics Division Special Heavy Ion Discussion Group: "Recoil Mass Separator at JAERI" by Hiroshi Ikezoe, Japan Atomic Energy Research Institute (JAERI), Ibaraki, Japan. 3:30 p.m., Bldg. 203, Conference Room R150.

Spring 1996 ACCA Biology Seminar Series: "Veterinary Toxicology and Animal Models" by Jane Davis, Aurora University, Ill. 7 p.m., Bldg. 223 Auditorium.

Wednesday, Feb. 21

Reactor Engineering Division Seminar: "Wavelet Reproducing Kernel Methods" by Wing Kam Liu, Department of Mechanical Engineering, Northwestern University, Evanston, Ill. 10 a.m., Bldg. 208, Conference Room A138.

High Energy Physics Division Seminar: "Results from the Study of CP, T, and CPT Symmetries with the CPLEAR Detector" by David Zimmerman, University of Minnesota, Minneapolis. 11 a.m., Bldg. 362, Conference Room F108.

Argonne Chapter of Sigma Xi Seminar: "Monitoring Charge Separation in Photosynthesis" by Marion C. Thurnauer, (CHM). Noon, Bldg. 203 Auditorium.

Energy Systems Division Seminar: "A New Photocatalytic Process for Heavy Metal Removal from Aqueous Waste Streams" by Natasha Meshkov, (ES). Noon, Bldg. 362, Conference Room E356.

Physics Division Seminar: "Alpha-Decay as a Probe to Study Shape Coexistence in the Z=82 Region" by Jan Wauters, University of Tennessee, Knoxville. 3:30 p.m., Bldg. 203, Conference Room R150.

Friday, Feb. 23

Physics Colloquium: "Recent Advances in the Study of Nuclear Clusters" by Alan H. Wuosmaa, (PHY). 11 a.m., Bldg. 203 Auditorium.

Monday, Feb. 26

Energy Technology Division Seminar: "Ultrasonic Technique for Fabric-Defect Inspection Application" by Hual-Te Chien, (ET). 10:30 a.m., Bldg. 212, Conference Room A157.

Chemistry Division Monday Morning Seminar Series: "Multiple Electron Transfer Rates from Vibrational Populations" by Kenneth Spears, Department of Chemistry, Northwestern University, Evanston, Ill. 11 a.m., Bldg. 200 Auditorium.

Chemistry Division Seminar: "The Design of New Solid-State NMR Experiments for Use in Determining Oligonucleotide Structure" by David Gregory, University of Washington, Seattle. 1:30 p.m., Bldg. 200, Conference Room J183.

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