Walter Henry Zinn (December 10, 1906 – February 14, 2000) was an American
nuclear physicist
Nuclear physics is the field of physics that studies atomic nuclei and their constituents and interactions, in addition to the study of other forms of nuclear matter.
Nuclear physics should not be confused with atomic physics, which studies the ...
who was the first director of the
Argonne National Laboratory
Argonne National Laboratory is a science and engineering research United States Department of Energy National Labs, national laboratory operated by University of Chicago, UChicago Argonne LLC for the United States Department of Energy. The facil ...
from 1946 to 1956. He worked at the
Manhattan Project
The Manhattan Project was a research and development undertaking during World War II that produced the first nuclear weapons. It was led by the United States with the support of the United Kingdom and Canada. From 1942 to 1946, the project w ...
's
Metallurgical Laboratory
The Metallurgical Laboratory (or Met Lab) was a scientific laboratory at the University of Chicago that was established in February 1942 to study and use the newly discovered chemical element plutonium. It researched plutonium's chemistry and m ...
during
World War II
World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposin ...
, and supervised the construction of
Chicago Pile-1
Chicago Pile-1 (CP-1) was the world's first artificial nuclear reactor. On 2 December 1942, the first human-made self-sustaining nuclear chain reaction was initiated in CP-1, during an experiment led by Enrico Fermi. The secret development of t ...
, the world's first
nuclear reactor
A nuclear reactor is a device used to initiate and control a fission nuclear chain reaction or nuclear fusion reactions. Nuclear reactors are used at nuclear power plants for electricity generation and in nuclear marine propulsion. Heat from nu ...
, which
went critical on December 2, 1942, at the
University of Chicago
The University of Chicago (UChicago, Chicago, U of C, or UChi) is a private research university in Chicago, Illinois. Its main campus is located in Chicago's Hyde Park neighborhood. The University of Chicago is consistently ranked among the b ...
. At Argonne he designed and built several new reactors, including
Experimental Breeder Reactor I
Experimental Breeder Reactor I (EBR-I) is a decommissioned research reactor and U.S. National Historic Landmark located in the desert about southeast of Arco, Idaho. It was the world's first breeder reactor. At 1:50 p.m. on December 20, 1 ...
, the first nuclear reactor to produce electric power, which went live on December 20, 1951.
Early life
Walter Henry Zinn was born in
Berlin (now Kitchener), Ontario, on December 10, 1906, the son of John Zinn, who worked in a tire factory, and Maria Anna Stoskopf. He had an older brother, Albert, who also became a factory worker.
Zinn entered
Queen's University, where he earned a
Bachelor of Arts
Bachelor of arts (BA or AB; from the Latin ', ', or ') is a bachelor's degree awarded for an undergraduate program in the arts, or, in some cases, other disciplines. A Bachelor of Arts degree course is generally completed in three or four years ...
degree in mathematics in 1927 and a
Master of Arts
A Master of Arts ( la, Magister Artium or ''Artium Magister''; abbreviated MA, M.A., AM, or A.M.) is the holder of a master's degree awarded by universities in many countries. The degree is usually contrasted with that of Master of Science. Tho ...
degree in 1930. He then entered
Columbia University
Columbia University (also known as Columbia, and officially as Columbia University in the City of New York) is a private research university in New York City. Established in 1754 as King's College on the grounds of Trinity Church in Manhatt ...
in 1930, where he studied physics,
writing his
Doctor of Philosophy
A Doctor of Philosophy (PhD, Ph.D., or DPhil; Latin: or ') is the most common Academic degree, degree at the highest academic level awarded following a course of study. PhDs are awarded for programs across the whole breadth of academic fields ...
thesis on "Two-crystal study of the structure and width of K X-ray absorption limits".
This was subsequently published in the ''
Physical Review
''Physical Review'' is a peer-reviewed scientific journal established in 1893 by Edward Nichols. It publishes original research as well as scientific and literature reviews on all aspects of physics. It is published by the American Physical S ...
''.
To support himself, Zinn taught at Queen's University from 1927 to 1928, and at Columbia from 1931 to 1932. He became an instructor at the
City College of New York
The City College of the City University of New York (also known as the City College of New York, or simply City College or CCNY) is a public university within the City University of New York (CUNY) system in New York City. Founded in 1847, Cit ...
in 1932. While at Queen's he met Jennie A. (Jean) Smith, a fellow student. They were married in 1933 and had two sons, John Eric and Robert James. In 1938, Zinn became a
naturalised
Naturalization (or naturalisation) is the legal act or process by which a non-citizen of a country may acquire citizenship or nationality of that country. It may be done automatically by a statute, i.e., without any effort on the part of the i ...
United States citizen.
Manhattan Project
In 1939, the
Pupin Physics Laboratories at Columbia where Zinn worked were the center of intensive research into the properties of
uranium
Uranium is a chemical element with the symbol U and atomic number 92. It is a silvery-grey metal in the actinide series of the periodic table. A uranium atom has 92 protons and 92 electrons, of which 6 are valence electrons. Uranium is weak ...
and
nuclear fission
Nuclear fission is a reaction in which the nucleus of an atom splits into two or more smaller nuclei. The fission process often produces gamma photons, and releases a very large amount of energy even by the energetic standards of radio ...
, which had recently been discovered by
Lise Meitner
Elise Meitner ( , ; 7 November 1878 – 27 October 1968) was an Austrian-Swedish physicist who was one of those responsible for the discovery of the element protactinium and nuclear fission. While working at the Kaiser Wilhelm Institute on rad ...
,
Otto Hahn
Otto Hahn (; 8 March 1879 – 28 July 1968) was a German chemist who was a pioneer in the fields of radioactivity and radiochemistry. He is referred to as the father of nuclear chemistry and father of nuclear fission. Hahn and Lise Meitner ...
and
Fritz Strassmann
Friedrich Wilhelm Strassmann (; 22 February 1902 – 22 April 1980) was a German chemist who, with Otto Hahn in December 1938, identified the element barium as a product of the bombardment of uranium with neutrons. Their observation was the key ...
. At Columbia, Zinn,
Enrico Fermi
Enrico Fermi (; 29 September 1901 – 28 November 1954) was an Italian (later naturalized American) physicist and the creator of the world's first nuclear reactor, the Chicago Pile-1. He has been called the "architect of the nuclear age" and ...
,
Herbert L. Anderson
Herbert Lawrence Anderson (May 24, 1914 – July 16, 1988) was an American nuclear physicist who was Professor of Physics at the University of Chicago.
He contributed to the Manhattan Project. He was also a member of the team which made the firs ...
,
John R. Dunning and
Leo Szilard
Leo Szilard (; hu, Szilárd Leó, pronounced ; born Leó Spitz; February 11, 1898 – May 30, 1964) was a Hungarian-German-American physicist and inventor. He conceived the nuclear chain reaction in 1933, patented the idea of a nuclear ...
investigated whether
uranium-238
Uranium-238 (238U or U-238) is the most common isotope of uranium found in nature, with a relative abundance of 99%. Unlike uranium-235, it is non-fissile, which means it cannot sustain a chain reaction in a thermal-neutron reactor. However, it ...
fissioned with slow neutrons, as Fermi believed, or only the
uranium-235
Uranium-235 (235U or U-235) is an isotope of uranium making up about 0.72% of natural uranium. Unlike the predominant isotope uranium-238, it is fissile, i.e., it can sustain a nuclear chain reaction. It is the only fissile isotope that exis ...
isotope
Isotopes are two or more types of atoms that have the same atomic number (number of protons in their nuclei) and position in the periodic table (and hence belong to the same chemical element), and that differ in nucleon numbers (mass numbers) ...
, as
Niels Bohr
Niels Henrik David Bohr (; 7 October 1885 – 18 November 1962) was a Danish physicist who made foundational contributions to understanding atomic structure and quantum theory, for which he received the Nobel Prize in Physics in 1922. B ...
contended. Since pure uranium-235 was not available, Fermi and Szilard chose to work with natural uranium. They were particularly interested in whether a
nuclear chain reaction
In nuclear physics, a nuclear chain reaction occurs when one single nuclear reaction causes an average of one or more subsequent nuclear reactions, thus leading to the possibility of a self-propagating series of these reactions. The specific nu ...
could be initiated. This would require more than one
neutron
The neutron is a subatomic particle, symbol or , which has a neutral (not positive or negative) charge, and a mass slightly greater than that of a proton. Protons and neutrons constitute the nuclei of atoms. Since protons and neutrons beh ...
to be emitted per fission on average in order to keep the chain reaction going. By March 1939, they established that about two were being emitted per fission on average. The delay between an atom absorbing a neutron and fission occurring would be the key to controlling a chain reaction.
At this point Zinn began working for Fermi, constructing experimental uranium
lattice
Lattice may refer to:
Arts and design
* Latticework, an ornamental criss-crossed framework, an arrangement of crossing laths or other thin strips of material
* Lattice (music), an organized grid model of pitch ratios
* Lattice (pastry), an ornam ...
s.
To slow neutrons down requires a
neutron moderator
In nuclear engineering, a neutron moderator is a medium that reduces the speed of fast neutrons, ideally without capturing any, leaving them as thermal neutrons with only minimal (thermal) kinetic energy. These thermal neutrons are immensely mo ...
. Water was Fermi's first choice, but it tended to absorb neutrons as well as slow them. In July, Szilard suggested using
carbon
Carbon () is a chemical element with the symbol C and atomic number 6. It is nonmetallic and tetravalent
In chemistry, the valence (US spelling) or valency (British spelling) of an element is the measure of its combining capacity with o ...
, in the form of
graphite
Graphite () is a crystalline form of the element carbon. It consists of stacked layers of graphene. Graphite occurs naturally and is the most stable form of carbon under standard conditions. Synthetic and natural graphite are consumed on large ...
. The critical radius of a spherical reactor was calculated to be:
:
In order for a
self-sustaining nuclear chain reaction
In nuclear physics, a nuclear chain reaction occurs when one single nuclear reaction causes an average of one or more subsequent nuclear reactions, thus leading to the possibility of a self-propagating series of these reactions. The specific nu ...
to occur, they needed k > 1. For a practical reactor configuration, it needed to be at least 3 or 4 percent more; but in August 1941 Zinn's initial experiments indicated a disappointing value of 0.87. Fermi pinned his hopes of a better result on an improved configuration, and purer uranium and graphite.
In early 1942, with the United States now embroiled
World War II
World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposin ...
,
Arthur Compton
Arthur Holly Compton (September 10, 1892 – March 15, 1962) was an American physicist who won the Nobel Prize in Physics in 1927 for his 1923 discovery of the Compton effect, which demonstrated the particle nature of electromagnetic radia ...
concentrated the
Manhattan Project
The Manhattan Project was a research and development undertaking during World War II that produced the first nuclear weapons. It was led by the United States with the support of the United Kingdom and Canada. From 1942 to 1946, the project w ...
's various teams working on
plutonium
Plutonium is a radioactive chemical element with the symbol Pu and atomic number 94. It is an actinide metal of silvery-gray appearance that tarnishes when exposed to air, and forms a dull coating when oxidized. The element normally exhibi ...
at the
Metallurgical Laboratory
The Metallurgical Laboratory (or Met Lab) was a scientific laboratory at the University of Chicago that was established in February 1942 to study and use the newly discovered chemical element plutonium. It researched plutonium's chemistry and m ...
at the
University of Chicago
The University of Chicago (UChicago, Chicago, U of C, or UChi) is a private research university in Chicago, Illinois. Its main campus is located in Chicago's Hyde Park neighborhood. The University of Chicago is consistently ranked among the b ...
. Zinn used athletes to build Fermi's increasingly large experimental configurations under the stands of the disused
Stagg Field
Amos Alonzo Stagg Field is the name of two successive football fields for the University of Chicago. Beyond sports, the first Stagg Field (1893–1957) is remembered for its role in a landmark scientific achievement of Enrico Fermi and the Metall ...
.
In July 1942, Fermi measured a k = 1.007 from a
uranium oxide
Uranium oxide is an oxide of the element uranium.
The metal uranium forms several oxides:
* Uranium dioxide or uranium(IV) oxide (UO2, the mineral uraninite or pitchblende)
* Diuranium pentoxide or uranium(V) oxide (U2O5)
* Uranium trioxide or u ...
lattice. This raised hopes that pure uranium would yield a suitable value of k.
By December 1942, Zinn and Anderson had the new configuration ready at Stagg Field. Some long, wide and high, it contained of graphite and of uranium metal and uranium oxide.
When the experiment was carried out on the afternoon of December 2, 1942, the reactor, known as
Chicago Pile-1
Chicago Pile-1 (CP-1) was the world's first artificial nuclear reactor. On 2 December 1942, the first human-made self-sustaining nuclear chain reaction was initiated in CP-1, during an experiment led by Enrico Fermi. The secret development of t ...
, reached criticality without incident.
Since the reactor had no
radiation shield
Radiation protection, also known as radiological protection, is defined by the International Atomic Energy Agency (IAEA) as "The protection of people from harmful effects of exposure to ionizing radiation, and the means for achieving this". Exposur ...
, it was run at a maximum power of only 200 W, enough to power a light bulb, and ran for only three months. It was shut down on February 28, 1943, because the
US Army
The United States Army (USA) is the land service branch of the United States Armed Forces. It is one of the eight U.S. uniformed services, and is designated as the Army of the United States in the U.S. Constitution.Article II, section 2, cla ...
did not want to risk an accident near densely populated downtown Chicago.
The Army leased a of the
Cook County Forest Preserves
The Forest Preserve District of Cook County is a governmental commission in Cook County, Illinois, that owns and manages a network of open spaces, containing forest, prairie, wetland, streams, and lakes, that are mostly set aside as natural area ...
known as "
Site A" to the Manhattan Project, and "the Country Club" to the hundred or so scientists, guards and others who worked there. Zinn was placed in charge of Site A, under Fermi. Chicago Pile-1 was disassembled and rebuilt, this time with a radiation shield, at Site A. The reactor, now known as Chicago Pile-2, was operational again on March 20, 1943. Within a few months, Fermi began designing a new reactor, which became known as
Chicago Pile-3
Chicago Pile-3 (CP-3) was the world's first heavy water reactor. One of the first research reactors, it was built in 1943 near Palos Hills, Illinois, original site of Argonne National Laboratory. Joining CP-1/CP-2, it first went critical on 15 ...
. This was a very different type of reactor. It was much smaller, being only in diameter and high. It was power by 120 uranium metal rods, and moderated by of
heavy water.
Once again Zinn was in charge of construction, which commenced on New Year's Day in 1944. Chicago Pile-3 went critical on May 15, 1944, and commenced operation on June 23 at its full power of 300 KW. When Fermi departed for the
Hanford Site
The Hanford Site is a decommissioned nuclear production complex operated by the United States federal government on the Columbia River in Benton County in the U.S. state of Washington. The site has been known by many names, including SiteW a ...
, Zinn became the sole authority at Site A.
On September 29, 1944, Zinn received an urgent call from
Samuel Allison
Samuel King Allison (November 13, 1900 – September 15, 1965) was an American physicist, most notable for his role in the Manhattan Project, for which he was awarded the Medal for Merit. He was director of the Metallurgical Laboratory from 1943 ...
, the director of the Metallurgical Laboratory. The
B Reactor
The B Reactor at the Hanford Site, near Richland, Washington, was the first large-scale nuclear reactor ever built. The project was a key part of the Manhattan Project, the United States nuclear weapons development program during World War II. I ...
at Hanford had shut down shortly after reaching full power, only to come back to life again some hours later.
Norman Hilberry
Norman Hilberry (March 11, 1899 – March 28, 1986) was an American physicist, best known as the director of the Argonne National Laboratory from 1956 to 1961. In December 1942 he was the man who stood ready with an axe to cut the scram line duri ...
suspected a
neutron poison
In applications such as nuclear reactors, a neutron poison (also called a neutron absorber or a nuclear poison) is a substance with a large neutron absorption cross-section. In such applications, absorbing neutrons is normally an undesirable eff ...
was responsible. If so, it had a
half life
Half-life (symbol ) is the time required for a quantity (of substance) to reduce to half of its initial value. The term is commonly used in nuclear physics to describe how quickly unstable atoms undergo radioactive decay or how long stable at ...
of around 9.7 hours.
Xenon-135
Xenon-135 (135Xe) is an unstable isotope of xenon with a half-life of about 9.2 hours. 135Xe is a fission product of uranium and it is the most powerful known neutron-absorbing nuclear poison (2 million barns; up to 3 million barns under reactor c ...
had a half life close to that, but had not been detected in Argonne or by the
X-10 Graphite Reactor in
Oak Ridge, Tennessee
Oak Ridge is a city in Anderson and Roane counties in the eastern part of the U.S. state of Tennessee, about west of downtown Knoxville. Oak Ridge's population was 31,402 at the 2020 census. It is part of the Knoxville Metropolitan Area. Oak ...
. 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.
Over the following months, some 175 technical personnel were transferred from the Metallurgical Laboratory to Hanford and
Los Alamos. Zinn's Argonne Laboratory was reduced to a skeleton staff, but Compton would not countenance its closure.
Argonne National Laboratory
![Argonne history At the controls of Chicago Pile-3](https://upload.wikimedia.org/wikipedia/commons/9/95/Argonne_history_At_the_controls_of_Chicago_Pile-3.jpg)
On July 11, 1946, the Argonne laboratory officially became the
Argonne National Laboratory
Argonne National Laboratory is a science and engineering research United States Department of Energy National Labs, national laboratory operated by University of Chicago, UChicago Argonne LLC for the United States Department of Energy. The facil ...
, with Zinn as its first director.
Alvin Weinberg characterized Zinn as "a model of what a director of the then-emerging national laboratories should be: sensitive to the aspirations of both contractor and fund provider, but confident enough to prevail when this was necessary."
One of the first problems confronting Zinn was that of accommodation. The Federal government had promised to restore Site A to the Cook County Forest Preserves after the war, and despite intervention from the
Secretary of War
The secretary of war was a member of the U.S. president's Cabinet, beginning with George Washington's administration. A similar position, called either "Secretary at War" or "Secretary of War", had been appointed to serve the Congress of the ...
,
Robert P. Patterson
Robert Porter Patterson Sr. (February 12, 1891 – January 22, 1952) was an American judge who served as United States Under Secretary of War, Under Secretary of War under President Franklin D. Roosevelt and US Secretary of War, U.S. Secretary of ...
, the most the Cook County Forest Preserves Commission would agree to was that the Argonne National Laboratory could continue to occupy a portion of the lease until a new site was found. Zinn rejected alternate sites outside the Chicago area, and the Army found a new site for the laboratory's permanent home about away in
DuPage County, Illinois
DuPage County ( ) is a county in the U.S. state of Illinois, and one of the collar counties of the Chicago metropolitan area. As of the 2020 census, the population was 932,877, making it Illinois' second-most populous county. Its county seat is ...
, which became known as Site D.
Under Zinn, the Argonne National Laboratory adopted slightly more progressive hiring practices than other contemporary institutions. Three
African American
African Americans (also referred to as Black Americans and Afro-Americans) are an ethnic group consisting of Americans with partial or total ancestry from sub-Saharan Africa. The term "African American" generally denotes descendants of ens ...
women and seven men, six of whom had worked on the Manhattan Project, were employed in research at Argonne at a time when the
Los Alamos National Laboratory
Los Alamos National Laboratory (often shortened as Los Alamos and LANL) is one of the sixteen research and development laboratories of the United States Department of Energy (DOE), located a short distance northwest of Santa Fe, New Mexico, ...
had no African American scientists. Argonne also appointed women to positions of authority, with
Maria Goeppert-Mayer
Maria Goeppert Mayer (; June 28, 1906 – February 20, 1972) was a German-born American theoretical physicist, and Nobel laureate in Physics for proposing the nuclear shell model of the atomic nucleus. She was the second woman to win a Nobel Pri ...
as a section leader in the theoretical physics division, and
Hoylande Young as director of the technical information division.
The
Atomic Energy Commission (AEC) replaced the Manhattan Project on January 1, 1947, and on January 1, 1948 it announced that the Argonne National Laboratory would be "focused chiefly on problems of reactor development." Zinn did not seek the additional responsibility, which he realised would divert the Laboratory away from research, and divert him from other responsibilities, such as designing a
fast breeder
A breeder reactor is a nuclear reactor that generates more fissile material than it consumes. Breeder reactors achieve this because their neutron economy is high enough to create more fissile fuel than they use, by irradiation of a fertile mate ...
reactor. He even obtained a written assurance from
Carroll L. Wilson Carroll L. Wilson (September 21, 1910 – January 12, 1983; aged 72) was a Professor of Management at the Sloan School and the first Mitsui Professor in Problems of Contemporary Technology at MIT
The Massachusetts Institute of Technology (MI ...
, the AEC's general manager, that it would not. He was therefore willing to collaborate with Alvin Weinberg to allow the
Oak Ridge National Laboratory
Oak Ridge National Laboratory (ORNL) is a U.S. multiprogram science and technology national laboratory sponsored by the U.S. Department of Energy (DOE) and administered, managed, and operated by UT–Battelle as a federally funded research and ...
to remain involved in reactor design. Nonetheless, reactor research accounted for almost half the laboratory's budget in 1949, and 84 percent of its research was classified.
Zinn did not get along well with
Captain
Captain is a title, an appellative for the commanding officer of a military unit; the supreme leader of a navy ship, merchant ship, aeroplane, spacecraft, or other vessel; or the commander of a port, fire or police department, election precinct, e ...
Hyman G. Rickover
Hyman G. Rickover (January 27, 1900 – July 8, 1986) was an admiral in the U.S. Navy. He directed the original development of naval nuclear propulsion and controlled its operations for three decades as director of the U.S. Naval Reactors offic ...
, the
US Navy
The United States Navy (USN) is the maritime service branch of the United States Armed Forces and one of the eight uniformed services of the United States. It is the largest and most powerful navy in the world, with the estimated tonnage of ...
's Director of
Naval Reactors
Naval Reactors (NR), also known as the Naval Nuclear Propulsion Program, is an umbrella term for the U.S. government office that has comprehensive responsibility for the safe and reliable operation of the United States Navy's nuclear propulsion p ...
, but nonetheless Argonne assisted in the development of
nuclear marine propulsion
Nuclear marine propulsion is propulsion of a ship or submarine with heat provided by a nuclear reactor. The power plant heats water to produce steam for a turbine used to turn the ship's propeller through a gearbox or through an electric generato ...
, eventually producing two reactors, a land-based prototype Mark I and a propulsion reactor, the Mark II. The STR (Submarine Thermal Reactor)
pressurized water reactor
A pressurized water reactor (PWR) is a type of light-water reactor, light-water nuclear reactor. PWRs constitute the large majority of the world's nuclear power plants (with notable exceptions being the UK, Japan and Canada). In a PWR, the primary ...
designed at Argonne powered the first nuclear-powered
submarine
A submarine (or sub) is a watercraft capable of independent operation underwater. It differs from a submersible, which has more limited underwater capability. The term is also sometimes used historically or colloquially to refer to remotely op ...
, , and became the basis of nearly all the reactors installed in warships.
The other branch of reactor development at the Argonne National Laboratory, and the one closer to Zinn's heart, was the fast breeder reactor. At the time it was believed that uranium was a scarce resource, so it would be wise to make the best use of it. The breeders were designed to create more
fissile
In nuclear engineering, fissile material is material capable of sustaining a nuclear fission chain reaction. By definition, fissile material can sustain a chain reaction with neutrons of thermal energy. The predominant neutron energy may be typ ...
material than they consumed.
By 1948, he had become convinced that it would be unwise to build large experimental reactors near Chicago, and the AEC acquired land around
Arco, Idaho
Arco is a city in Butte County, Idaho, United States. The population was 879 as of the 2020 United States census, down from 995 at the 2010 census. Arco is the county seat and largest city in Butte County.
History
Originally known as Root Ho ...
, which became an outpost of Argonne. The
Experimental Breeder Reactor I
Experimental Breeder Reactor I (EBR-I) is a decommissioned research reactor and U.S. National Historic Landmark located in the desert about southeast of Arco, Idaho. It was the world's first breeder reactor. At 1:50 p.m. on December 20, 1 ...
(EBR-I, but known at Argonne as "ZIP" — Zinn's Infernal Pile) was the first reactor to be cooled by liquid metal,
and the first to produce electricity. It proved the breeder concept.
AEC Chairman
Gordon Dean described it as a major milestone in nuclear history.
The
BORAX Experiments
The BORAX Experiments were a series of safety experiments on boiling water nuclear reactors conducted by Argonne National Laboratory in the 1950s and 1960s at the National Reactor Testing Station in eastern Idaho. were a series of destructive tests of
boiling water reactors
A boiling water reactor (BWR) is a type of light water nuclear reactor used for the generation of electrical power. It is a design different from a Soviet graphite-moderated RBMK. It is the second most common type of electricity-generating nuc ...
conducted by Argonne National Laboratory in Idaho. The BORAX-1 test was conducted under Zinn's supervision in 1954. He 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. He shouted to Harold Lichtenberg to put the control rods back in again, but Lichtenberg pointed out that one was already flying through the air. Zinn later had to testify on the experiment before the
Joint Committee on Atomic Energy The Joint Committee on Atomic Energy (JCAE) was a United States congressional committee that was tasked with exclusive jurisdiction over "all bills, resolutions, and other matters" related to civilian and military aspects of nuclear power from 1946 ...
.
Later life
After leaving the Argonne National Laboratory in 1956, Zinn moved to Florida, where he founded his own consulting firm, General Nuclear Engineering,
with its headquarters in
Dunedin, Florida
Dunedin is a city in Pinellas County, Florida, United States. The name comes from ''Dùn Èideann'', the Scottish Gaelic name for Edinburgh, the capital of Scotland. Dunedin is part of the Tampa-St. Petersburg-Clearwater metropolitan area and is ...
. The company was involved in the design and construction of pressurized water reactors.
It was acquired by
Combustion Engineering
Combustion Engineering (C-E) was a multi-national American-based engineering firm that developed nuclear steam supply power systems in the United States. Originally headquartered in New York City, C-E moved its corporate offices to Stamford, Connec ...
in 1964, and he became a vice president and head of its nuclear division.
He stepped down from this position in 1970, but remained a board member until 1986. He served as a member of the
President's Science Advisory Committee
The President's Science Advisory Committee (PSAC) was created on November 21, 1957, by President of the United States Dwight D. Eisenhower, as a direct response to the Soviet launching of the Sputnik 1 and Sputnik 2 satellites. PSAC was an upgrade ...
from 1960 to 1962, and a member of the General Advisory Committee of the AEC and its successor, the
Energy Research and Development Administration
The United States Energy Research and Development Administration (ERDA) was a United States government organization formed from the split of the United States Atomic Energy Commission, Atomic Energy Commission (AEC) in 1975. It assumed the functio ...
, from 1972 to 1975.
Over the years Zinn received multiple awards for his work, including a special commendation from the AEC in 1956, the
Atoms for Peace Award
The Atoms for Peace Award was established in 1955 through a grant of $1,000,000 by the Ford Motor Company Fund. An independent nonprofit corporation was set up to administer the award for the development or application of peaceful nuclear technol ...
in 1960,
the
Enrico Fermi Award
The Enrico Fermi Award is a scientific award conferred by the President of the United States. It is awarded to honor scientists of international stature for their lifetime achievement in the development, use, or production of energy. It was establ ...
in 1969, and the
Elliott Cresson Medal
The Elliott Cresson Medal, also known as the Elliott Cresson Gold Medal, was the highest award given by the Franklin Institute. The award was established by Elliott Cresson, life member of the Franklin Institute, with $1,000 granted in 1848. The ...
from
The Franklin Institute
The Franklin Institute is a science museum and the center of science education and research in Philadelphia, Pennsylvania. It is named after the American scientist and statesman Benjamin Franklin. It houses the Benjamin Franklin National Memoria ...
in 1970.
In 1955 he was elected as the first president of the
American Nuclear Society
The American Nuclear Society (ANS) is an international, not-for-profit organization of scientists, engineers, and industry professionals that promote the field of nuclear engineering and related disciplines.
ANS is composed of three communities ...
(ANS).
Zinn's wife Jean died in 1964.
He married Mary Teresa Pratt in 1966, and thereby acquired two stepsons, Warren and Robert Johnson.
He died in
Mease Countryside Hospital in
Safety Harbor, Florida
Safety Harbor is a city on the west shore of Tampa Bay in Pinellas County, Florida, United States. It was settled in 1823 and incorporated in 1917. The population was 16,884 at the 2010 census.
History
The area has been inhabited since the Stone ...
, on February 14, 2000, after suffering a stroke. He was survived by his wife Mary, sons John and Robert and stepson Warren. Robert had become a professor of
astronomy
Astronomy () is a natural science that studies astronomical object, celestial objects and phenomena. It uses mathematics, physics, and chemistry in order to explain their origin and chronology of the Universe, evolution. Objects of interest ...
at
Yale University
Yale University is a private research university in New Haven, Connecticut. Established in 1701 as the Collegiate School, it is the third-oldest institution of higher education in the United States and among the most prestigious in the wo ...
.
Walter H. Zinn Award
Since 1976, the American Nuclear Society's Operations and Power Division, has annually presented the Walter H. Zinn Award to recognize an individual "for a notable and sustained contribution to the nuclear power industry that has not been widely recognized."
Notes
References
*
*
*
{{DEFAULTSORT:Zinn, Walter
1906 births
2000 deaths
Scientists from Kitchener, Ontario
Columbia Graduate School of Arts and Sciences alumni
Queen's University at Kingston alumni
City College of New York faculty
Canadian nuclear physicists
American nuclear physicists
Manhattan Project people
Atoms for Peace Award recipients
Columbia University faculty