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60-Year-Old Film Surfaces, Depicting Discovery of Mendelevium

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Mend— By Sabin Russell

A reel of black & white film shot nearly 60 years ago has surfaced at Berkeley Lab, depicting the discovery of Mendelevium — or Element 101 — as reenacted by some of the legendary scientists who did the actual work at that time. Since the 1940s, Berkeley Lab scientists were locked in a race to synthesize new elements, and more often than not, they came out winners. Sixteen elements, most of them in the actinide series at the bottom of the periodic table, were discovered and synthesized by its researchers.

Retired Berkeley Lab physicist Claude Lyneis found the reel in a box of dusty and deteriorating films slated for disposal. Using digital editing skills he acquired to make videos of his son’s lacrosse team, Lyneis has produced and narrated an excerpt of this nearly-lost footage. It is an entertaining and informative look at the pioneering physics performed at UC Berkeley and Lawrence Berkeley National Laboratory’s hillside campus, known then as the UC Rad Lab.

Lyneis was Deputy Division Director for the Nuclear Science Division when he retired from Berkeley Lab three years ago. Yet he is still an affiliate at Building 88, where for years he was head of the Lab’s workhorse 88-Inch Cyclotron. While exploring the cardboard carton of films, one in particular caught his eye: 18 minutes of silent footage shot by KQED for UC Berkeley in 1955. “These are 16 mm films. They aren’t going to last. But they are part of our division’s history,” says Lyneis.

Lyneis believes the footage may have been shot for a documentary showing various experimental techniques used at the Rad Lab and E.O. Lawrence’s 60-inch cyclotron housed on the Berkeley campus. Whether that documentary was ever released remains unknown. The historic Berkeley cyclotron was eventually moved to UC Davis, where it has been running since 1966 at Crocker Nuclear Laboratory.

Lyneis first created a digital copy of the 18-minute original. Then, to make sense of his find, he added sound effects and narrated a shortened version of the old film. The reenactment stars some of the key Berkeley Lab scientists involved in the discovery of Mendelevium: Al Ghiorso, Bernard Harvey, Gregory Choppin, and team leader Stanley Thompson. With their director, Glenn Seaborg, who does not appear in the film, the group published their research in a June 1955 issue of Physical Review, which announced the discovery to the world.

When Lyneis started as a physicist at Berkeley Lab in 1982, these men were well-known giants in the field. “I knew Al Ghiorso,’’ Lyneis recalls. “I know Bernard Harvey. He still lives in Berkeley, and he was the one who hired me.”

To inform his narrative, Lyneis looked up old papers on the techniques shown in the film. His excerpt portrays in less than four minutes the cutting edge of nuclear science, as practiced in the mid 1950s by Berkeley Lab, where researchers discovered not only Mendelevium, but Berkelium, Californium, Einsteinium, Fermium, Nobelium, Lawrencium, and more.

The film opens on the Berkeley campus as Ghiorso is loading gold foil laced with Element 99, Einsteinium, into the 60-inch cyclotron. The target is bombarded with helium ions whipping around at near-lightspeed. A fraction of those ions fused with Einsteinium atoms, creating new isotopes and a few precious atoms of the new element with the atomic number 101. Ghiorso and Harvey are then seen rolling back the concrete radiation shielding, retrieving the targets, and rushing them up hill for analysis. In Berkeley Lab’s Building 70, the nuclear chemistry laboratory, they isolate and detect the newly forged atoms using an ion resin column technique. Once separated, the presence of Mendelevium atoms is revealed during their brief existence — with a half-life of 87 minutes — through detection of their radioactive decay.

The video clip brought back memories for Berkeley Lab engineer Bill Ghiorso, whose father, Al, was the engineering genius behind most of the Lab’s discoveries of new elements. That work was carried out under the guidance of the legendary Seaborg, who won the Nobel Prize in 1951 for the earliest discoveries of transuranium elements. “My dad had this enormous amount of energy,” he recalls. “If they ran into difficulties, he would throw all his efforts into it.” Bill Ghiorso was nine years old in 1955, but he remembers riding with his father in the VW bug on one of these many high-speed uphill runs from cyclotron to lab. “Dad installed a Judson supercharger on that VW,” he recalls. “We would drive to Yosemite in it, and it pulled a trailer.” Al Ghiorso died in 2010 at the age of 95.

Seaborg himself appears on another, longer film, which Lyneis found in the cardboard box. Shot in 1968 by Argonne National Laboratory, it documents the 25th anniversary of the commissioning of the top-secret nuclear reactor built in Hanford, Washington, to produce plutonium for the atomic bomb. The 45-minute color film, which is deteriorating because of a chemical process known as vinegarization, features panel discussions where Seaborg joins the Manhattan Project’s director, General Leslie Groves, and other key atomic scientists recalling the fateful decisions of those times. Lyneis is hopeful that he can find funding to carry out a full digital restoration of these and other films, which were otherwise likely headed for history’s famous dustbin.


Written by physicsgg

November 12, 2013 at 2:55 pm


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