Radiation, The University of Chicago and the Manhattan Project

By Steve Koppes
Photo by Robert Kozloff

The Atomic Age began at 3:25 p.m. on Dec. 2, 1942—quietly, in secrecy, on a squash court under the west stands of old Stagg Field at the University of Chicago.

Today, Henry Moore’s “Nuclear Energy” sculpture and the Mansueto Library occupy the area at the corner of Ellis Avenue and 57th Street where Enrico Fermi and his colleagues engineered the first controlled, self-sustaining nuclear chain reaction 70 years ago. Their experiment was a key step in the Manhattan Project to develop the atomic bomb during World War II.

That initial chain reaction was too weak to power even a single light bulb. It nevertheless transformed the world, and the University of Chicago along with it, in a range of endeavors spanning physics, chemistry, interdisciplinary research, policy analysis, and nuclear medicine. Even in 1942, those present at the historic event sensed how influential their work would be.

“All of us . . . knew that with the advent of the chain reaction, the world would never be the same again,” former UChicago physicist Samuel K. Allison wrote at the time.

That first chain reaction’s complex legacy includes the peaceful uses of nuclear energy, the terrible power of nuclear weapons, and a new era of other scientific and technological advances.

After the war, UChicago founded the Institute for Nuclear Studies and the Institute for the Study of Metals. Later renamed the Enrico Fermi and the James Franck institutes, they enabled the University to retain much of the intellectual talent that had assembled on campus to work on the Manhattan Project. Another outgrowth of the project was Argonne National Laboratory, which conducts basic and applied research in many major scientific disciplines. Today, Argonne is a partner in the Institute for Molecular Engineering, which is bringing leading scientists and engineers to a groundbreaking initiative to conduct research at the molecular level.

“What we see here is a legacy of connection that we’re still building upon, a way to try to redefine engineering for the 21st century," said Provost Thomas Rosenbaum, the John T. Wilson Distinguished Service Professor in Physics.

Building the pile

Though Fermi’s team was engaged in the biggest secret project of World War II, they discussed technical issues under a tree on the Main Quad, which they deemed safe from eavesdroppers. In the middle of the day on which they produced the first chain reaction, they took a customary lunch break at Hutchinson Commons.

“Don’t imagine that they were able to achieve a chain reaction on the first try,” says Roger Hildebrand, the Samuel K. Allison Distinguished Service Professor Emeritus in Physics. “They built and rebuilt stacks of uranium, uranium oxide, and graphite 30 times before they were ready for the final test.”

Chicago Pile Number One, or CP-1 for short, consisted of 40,000 graphite blocks that enclosed 19,000 pieces of uranium metal and uranium oxide fuel. The scientists of what was then called the Metallurgical Laboratory, or “Met Lab,” had arranged the graphite in layers within a 24-foot-square wooden framework.

Hildebrand had started his work on the Manhattan Project as an undergraduate chemistry major at the University of California, Berkeley. He worked for Nobel laureate Ernest Lawrence, namesake of the Lawrence Livermore and Lawrence Berkeley national laboratories, using Berkeley’s cyclotron accelerator to transmute uranium into plutonium, an element believed to have potential for driving a chain reaction.

The samples irradiated in Berkeley and another lab in St. Louis ended up in the James Herbert Jones Laboratory, just one block south of old Stagg Field. There, in Jones Lab’s Room 405, future Nobel laureate Glenn Seaborg achieved an important steppingstone on the way to the Atomic Age. He weighed the first visible, pinhead-sized sample of plutonium. It wasn’t much, but enough to measure its chemical and metallurgical properties.

The potential hazards of nuclear power were evident even in those early days, but the war effort took priority. The Japanese had bombed Pearl Harbor on Dec. 7, 1941. Germany and Italy declared war on the United States four days later.

“They were advancing everywhere, they were conquering everywhere, and they were working on an atomic bomb,” Hildebrand said of the Germans. “The consequence of losing a nuclear race was the preoccupation of everyone who knew that a nuclear bomb might be possible.”

Outgrowths of chain reaction success

The scientific staff of the Metallurgical Laboratory founded the Atomic Scientists of Chicago on Sept. 26, 1945—just weeks after the United States dropped the atomic bomb on Hiroshima and Nagasaki. The group published the first issue of the Bulletin of the Atomic Scientists of Chicagoon Dec. 10, 1945. The Bulletin’s Doomsday Clock still stands as a symbol of humanity’s vulnerability to man-made catastrophe, with an agenda that expanded from nuclear weapons to include climate change and biological weapons.

Medical research gained unexpected benefits from the wartime research. In the early 1950s, the Atomic Energy Commission funded the Argonne Cancer Research Hospital, which became the Franklin McLean Institute, 5841 S. Ellis Ave., in 1973. The Argonne Hospital successfully pioneered the use of radiation in cancer treatment, with efforts later expanding to include radiological innovations in the diagnosis and treatment of other diseases.

Although the University of Chicago already was renowned in physics and chemistry before World War II, scientists who worked on the Manhattan Project helped those departments attain new research prominence following the war. Numerous UChicago scientists who were part of the war effort won Nobel Prizes for scholarly work in the postwar period, including Owen Chamberlain, Eugene P. Wigner, and Glenn Seaborg. Fermi, one of the most important scientists of the 20th century, became an inspiring teacher at UChicago after the war before dying of stomach cancer in 1954. The National Accelerator Laboratory in Batavia was renamed in Fermi’s honor in 1974, and became known as Fermilab, the site of numerous fundamental advances in particle physics.

UChicago builds for the future

Today, the William Eckhart Research Center is rising from a construction site directly across the street from where Fermi and his associates achieved the first controlled, self-sustaining nuclear chain reaction. The Eckhart Center will occupy the site of the former Research Institutes building, where Fermi and many other Manhattan Project veterans did transformative research.

UChicago scientists formally honored the Research Institutes’ legacy in June 2011, when they publicly revealed the contents of the time capsule that Fermi had sealed within the Research Institutes building cornerstone nearly 62 years earlier. In retrospect the cornerstone’s contents, which included booklets on the institutes and a sketch of their building, barely hinted at the accomplishments that would follow. That inspiring legacy survives to this day, said Robert Fefferman, dean of the University’s Physical Sciences Division.

“This is not just something about the distant past,” Fefferman, remarked at the cornerstone unveiling ceremony. “This is something that continues, and we’re extremely proud of the grand tradition of science here.”


A pioneer in the use of radiation to treat cancer, Lester Skaggs, Ph.D., professor emeritus in the Departments of Radiology and of Radiation and Cellular Oncology at the University of Chicago Medical Center, died from complications of renal failure on Friday, April 3, at Mercy Hospital and Medical Center in Chicago. He was 97.

One of the original practitioners of medical physics, Skaggs and colleague Lawrence Lanzl designed and helped build the cobalt radiation therapy unit and a linear accelerator for medical use at the University of Chicago, the first such devices in the United States. Prior to that, he was a key member of the Manhattan Project, based during World War II at Los Alamos National Laboratory in New Mexico, where he helped design, build and test the mechanism used to detonate the first atomic bomb.

"Lester Skaggs was brilliant, one of the leaders in the field of medical physics and radiation therapy," said colleague Melvin Griem, M.D., professor emeritus of radiation and cellular oncology at the University. "He combined that brilliance with the ability to make everyone around him smarter," Griem said. "He made his colleagues blossom. He made us look great."

"He was like a second father to me," said Franca Kuchnir, Ph.D., professor emerita of radiation and cellular oncology at the University and one of Skaggs's first post-doctoral fellows. "Those of us who have studied under his guidance and worked with him have been enriched by his deep knowledge of medical physics, his full dedication to education and his generous sharing of common sense and wisdom," she said.

Born Nov. 21, 1911, in Trenton, Missouri, Lester S. Skaggs grew up on a farm in northern Missouri. He attended a one-room grade school and rode a horse three miles to high school. His father expected him, the oldest of three children, to take over the farm, but Skaggs enjoyed designing and building gadgets and opted instead for a career in science. He earned his bachelor's degree in chemistry from the University of Missouri in 1933 with a minor in mathematics, followed by a master's degree in physics in 1934. In 1935 he entered the nuclear physics graduate program at the University of Chicago, where he completed his Ph.D. in 1939.

Skaggs took a part-time job with a radiation oncologist at nearby Michael Reese Hospital while working as a post-doctoral fellow in nuclear physics at The University of Chicago. He was soon drafted into the war effort, however, working from 1941 to 1943 for the Department of Terrestrial Magnetism at the Carnegie Institute in Washington, DC, where he designed a system that used radio waves to detect proximity to an airplane and detonate anti-aircraft shells.

In 1943, he was transferred to the Los Alamos, New Mexico, headquarters of the Manhattan Project, the secret military effort led by Robert Oppenheimer to develop the atomic bomb. At Los Alamos, Skaggs was asked to adapt his anti-aircraft detection system into an infallible "fuse" for the first bomb. "He was told," Kuchnir said, "that the odds of the system failing should be no greater than one in a million."

After witnessing, from 20 miles away, the initial test explosion at Alamogordo, Skaggs realized that the initial plan did not leave enough time for the airplane that delivered the bomb to escape safely. "He had to find a fool-proof way to get that damn plane out of there," recalled Griem. So Skaggs and colleagues designed a proximity-based detonation device--triggered by distance from the ground, with two back-up systems--that allowed the plane another 30 seconds to get out of harm's way.

After the war, he increasingly focused on medical applications of radiation. In 1945, on loan from Michael Reese Hospital, he began working on a physics research project with Donald Kerst at the University of Illinois to extract an electron beam for medical use from a betatron, a radiation source Kerst had invented for physics experiments. A clinical application came sooner than expected. As the work progressed, one of the physics graduate students was diagnosed with a brain tumor for which there was no effective treatment. Skaggs was part of a team of scientists who quickly developed the technology to help their friend.

"This was a hush-hush affair," recalled Elisabeth Lanzl, who, with her husband Lawrence, was also part of the team. "It was all done late at night, after the staff had gone home. It was the first time high-energy radiation had been used for medical therapy. It was beneficial," she said, "shrinking the tumor," but not curative. "The young man did die from his cancer."

In 1948, Skaggs joined the faculty at The University of Chicago as an assistant professor of radiology. He was promoted to associate professor in 1949 and placed in charge of developing the radiation therapy facilities at the Argonne Cancer Research Hospital (ACRH), which was funded by the Atomic Energy Commission's "Atoms for Peace" program. When it opened in 1953, ACRH was the first hospital devoted to the use of radiation to treat cancer.

At ACRH, Skaggs and Lanzl designed a cobalt treatment unit, much of which they built in the ACRH and the University's physical sciences machine shops. Piece-by-piece installation of a linear accelerator, known as the Lineac followed. This required "eight years of design, engineering, construction and testing, at a cost of $450,000," said Kuchnir, but the unit, completed in 1959, attracted patients from all over the country. It provided "the greatest degree of control ever achieved over the penetration of high energy rays in medical use," according to the University's 1960 press release. The Lineac, which "consumed power equivalent to that of a town of 100,000," remained in clinical use for 34 years.

In the mid-1950's, Skaggs and Lanzl launched the first master's degree program in medical physics in the United States. The program expanded in the 1960's to include a Ph.D. degree in medical physics and trained many of the leaders in the field.

Skaggs, who was promoted to full professor status in 1956, also designed and built one of the first analog computers for calculating the radiation dose to various tissues for use in planning radiation therapy. Completed in 1963, the electronic components, including 26 amplifiers, filled a small room.

In the 1970s, Kuchnir and Skaggs developed a method to produce neutrons for radiation therapy. "Ours was the first hospital-based fast-neutron therapy facility in the United States," Kuchnir recalled.

For most of his Chicago career, Skaggs and his family lived in Park Forest, IL, where he was designated a "distinguished citizen" in 1965. He and his wife, Ruth, were active in civic and church affairs.

The author or co-author of nearly 50 research publications in scientific journals, Skaggs was a Fellow of the American Physical Society, the American Association for the Advancement of Science, the Royal College of Medicine and the American College of Radiology (Fellow in Physics).

In 1979, at age 67, after 30 years of service, Skaggs retired from the University and began a new job at King Faisal Specialist Hospital and Research Centre in Riyadh, Saudi Arabia, where he developed a neutron-therapy facility using a cyclotron. He returned to the U.S. in 1984.

- See more at: http://news.uchicago.edu/article/2009/04/14/medical-physics-pioneer-lest...


Dr. Kuchnir was born in Bulgaria where she spent her childhood. After WWII and 4 years under communist regime, she lived in Italy and Brazil before coming to the US to work towards a Ph. D. in Nuclear Physics under the direction of Alfred O. Hanson at the University of Illinois, Champaign-Urbana. Upon graduation, she spent 5 years at Argonne National Laboratory working on experimental Nuclear Physics applying neutron time-of-flight techniques.

In 1971, Dr. Kuchnir joined The University of Chicago. Her first responsibility as a Post-Doctoral Fellow was to develop a hospital based Neutron Therapy Facility, which operated successfully for over 10 years. During this period, she made significant contributions to research and development in neutron dosimetry. Over the years, Dr. Kuchnir was been actively involved in all aspects of research and development in clinical radiation physics as well as in the implementation of new techniques and programs. She also made significant contributions to education, teaching undergraduate and graduate students as well as technical and medical staff. Most recently, Dr. Kuchnir initiated a residency Program in Medical Physics, which she directed up to her retirement in January 2001.

Dr. Kuchnir was fluent in five languages, traveled extensively and with her husband, also a physicist, and raised two successful children. She mentored both professionally and personally a large number of young people with whom she kept in contact with over the years.


"Medical Physics before the Millennium" - presentation at AAPM Midwest Chapter meeting, April 27, 2013 - Powerpoint

"Medical Physics before the Millennium" - presentation at AAPM Midwest Chapter meeting, April 27, 2013 - Word