Ernest Lawrence

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Ernest O. Lawrence

Ernest Orlando Lawrence (August 8, 1901 – August 27, 1958) was an American physicist and Nobel Laureate best known for his invention, utilization, and improvement of the cyclotron beginning in 1929, and his later work in uranium-isotope separation in the Manhattan Project. He had a long-term association with the University of California as a physics professor. In 1939, Lawrence was awarded the Nobel Prize in Physics for his work on the cyclotron and its applications. Chemical element number 103 is named "lawrencium" in his honor. He was also the first recipient of the Sylvanus Thayer Award.[1]

1 Early Life
2 Cyclotron
3 World War II
4 Post-war Career and Legacy
5 External links

[edit] Early Life

Born in Canton, South Dakota, Lawrence attended St. Olaf College in Minnesota, but transferred to the University of South Dakota after his first year. He earned his bachelor's degree in 1922. He received his Ph.D. in physics at Yale University in 1925. He remained at Yale as a researcher on the photoelectric effect, becoming an assistant professor in 1927.

In 1928 he was appointed Associate Professor of Physics at the University of California, Berkeley, and two years later he became Professor, being the youngest at Berkeley. There, he was called the "Atom Smasher,"; the man who "held the key" to atomic energy. "He wanted to do 'big physics,' the kind of work that could only be done on a large scale with a lot of people involved," said Herbert York, the first director of the Lawrence Livermore laboratory, as quoted on the lab's official Web site.

[edit] Cyclotron

The invention that brought Lawrence to international fame started out as a sketch on a scrap of paper. While sitting in the library one evening, Lawrence glanced over a journal article and was intrigued by one of the diagrams. The idea was to produce very high energy particles required for atomic disintegration by means of a succession of very small "pushes." Lawrence told his colleagues that he had found a method for obtaining particles of very high energy without the use of any high voltage.

Diagram of cyclotron operation from Lawrence's 1934 patent.

The first model of Lawrence's cyclotron was made out of wire and sealing wax and probably cost $25 in all. And it worked: When Lawrence applied 2,000 volts of electricity to his makeshift cyclotron, he got 80,000-volt projectiles spinning around. Through his increasingly larger machines, Lawrence was able to provide the crucial equipment needed for experiments in high energy physics. Around this device, Lawrence built up his Radiation Laboratory, which would become one of the foremost laboratories for physics research. He received a patent for the cyclotron in 1934, which he assigned to the Research Corporation. In 1936 he became Director of the University's Radiation Laboratory and served until his death.

In November 1939, Lawrence was awarded the Nobel Prize in Physics for his work on the cyclotron and its applications. The award ceremony was held in Berkeley, California due to the war, with Lawrence receiving his medal from the Sweden's Consul General in San Francisco.

[edit] World War II

Giant calutron plants developed at Lawrence's laboratory were used at Site X during World War II to purify uranium for use in the first atomic bomb.

During World War II, Lawrence eagerly helped to ramp up the American investigation of the possibility of weapon by nuclear fission. His Rad Lab became one of the major centers for wartime atomic research, and it was Lawrence who first introduced J. Robert Oppenheimer into what would become the Manhattan Project. An early champion of the electromagnetic separation method to enrich uranium, Lawrence manufactured his calutrons — specialized forms of mass spectrometers — for the massive separation plants at Oak Ridge, Tennessee. His secretary, Helen Griggs married future Nobel chemistry laureate Glenn T. Seaborg in 1942 as they made their way to work on the Manhattan Project in Chicago.

[edit] Post-war Career and Legacy

After the war, Lawrence campaigned extensively for government sponsorship of large scientific programs. Lawrence was a forceful advocate of "Big Science" with its requirements for big machines and big money.

For his service to his country, Lawrence was the first recipient of the prestigious Sylvanus Thayer Award by the United States Military Academy in 1958.

In July 1958, President Eisenhower sent Lawrence to Geneva, Switzerland, to negotiate the suspension of nuclear weapons testing with the Soviet Union. Lawrence became ill while in Geneva and was forced to return to Berkeley. He died a month later in Palo Alto, California.

Just 23 days after his death, the Regents of the University of California voted to rename the Lawrence Livermore and Lawrence Berkeley Laboratories after him. Chemical element number 103, discovered at LBNL in 1961, is named "lawrencium" in his honor.