25 Facts About Walter Zinn

Walter Henry Zinn was an American nuclear physicist who was the first director of the Argonne National Laboratory from 1946 to 1956.

Walter Zinn worked at the Manhattan Project's Metallurgical Laboratory during World War II, and supervised the construction of Chicago Pile-1, the world's first nuclear reactor, which went critical on December 2,1942, at the University of Chicago.

Walter Henry Zinn was born in Berlin, Ontario, on December 10,1906, the son of John Zinn, who worked in a tire factory, and Maria Anna Stoskopf.

Walter Zinn had an older brother, Albert, who became a factory worker.

Walter Zinn then entered Columbia University in 1930, where he studied physics, writing his Doctor of Philosophy thesis on "Two-crystal study of the structure and width of K X-ray absorption limits".

Walter Zinn became an instructor at the City College of New York in 1932.

In 1939, the Pupin Physics Laboratories at Columbia where Walter Zinn worked were the center of intensive research into the properties of uranium and nuclear fission, which had recently been discovered by Lise Meitner, Otto Hahn and Fritz Strassmann.

At this point Walter Zinn began working for Fermi, constructing experimental uranium lattices.

Walter Zinn used athletes to build Fermi's increasingly large experimental configurations under the stands of the disused Stagg Field.

Once again Walter Zinn was in charge of construction, which commenced on New Year's Day in 1944.

On September 29,1944, Walter Zinn received an urgent call from Samuel Allison, the director of the Metallurgical Laboratory.

Walter Zinn quickly brought Chicago Pile-3 up to full power, and within twelve hours, had made a series of measurements that confirmed the Hanford results.

One of the first problems confronting Walter Zinn was that of accommodation.

Walter Zinn even obtained a written assurance from Carroll L Wilson, the AEC's general manager, that it would not.

Walter Zinn was therefore willing to collaborate with Alvin Weinberg to allow the Oak Ridge National Laboratory to remain involved in reactor design.

The other branch of reactor development at the Argonne National Laboratory, and the one closer to Walter Zinn's heart, was the fast breeder reactor.

Walter Zinn had the control rods removed to demonstrate that the reactor would shut down without trouble, and it immediately blew up with a loud bang and a tall column of dark smoke, a turn of events that he had not anticipated.

Walter Zinn shouted to Harold Lichtenberg to put the control rods back in again, but Lichtenberg pointed out that one was already flying through the air.

Walter Zinn later had to testify on the experiment before the Joint Committee on Atomic Energy.

Walter Zinn was involved in the design and construction of pressurized water reactors.

Walter Zinn stepped down from this position in 1970, but remained a board member until 1986.

Walter Zinn served as a member of the President's Science Advisory Committee from 1960 to 1962, and a member of the General Advisory Committee of the AEC and its successor, the Energy Research and Development Administration, from 1972 to 1975.

Walter Zinn married Mary Teresa Pratt in 1966, and thereby acquired two stepsons, Warren and Robert Johnson.

Walter Zinn died in Mease Countryside Hospital in Safety Harbor, Florida, on February 14,2000, after suffering a stroke.

Walter Zinn was survived by his wife Mary, sons John and Robert and stepson Warren.