Kendall, Henry Way

▪ 2000

      American nuclear physicist (b. Dec. 9, 1926, Boston, Mass.—d. Feb. 15, 1999, near Tallahassee, Fla.), shared (with Jerome Isaac Friedman and Richard E. Taylor) the 1990 Nobel Prize for Physics for experiments confirming the existence of the subatomic particles known as quarks, the presence of which had been independently postulated in 1964 by Murray Gell-Mann and George Zweig. After attending (1945–46) the U.S. Merchant Marine Academy, Kendall graduated (B.A., 1950) from Amherst (Mass.) College and then dealt with electromagnetic interactions while pursuing his thesis at the Massachusetts Institute of Technology (Ph.D., 1955). After joining the research faculty at Stanford University under the tutelage of 1961 Nobel Prize winner Robert Hofstadter, he met Friedman and Taylor, and the three began their collaboration. In 1967, using the newly constructed Stanford Linear Accelerator Center and the east-coast facilities of MIT (where Kendall was made a full professor), they made pioneering measurements of highly inelastic electron scattering—that is, examination of the process of energy loss from “targets” of liquid hydrogen and deuterium, which were bombarded by electron beams. The way that the electrons scattered from the targets' constituent protons and neutrons confirmed that the latter particles were composed of still smaller entities, which Gell-Mann had dubbed quarks. Their experiments contradicted prevailing theories of subatomic structure and instigated a wide-ranging program of theoretical and experimental work that produced the constituent quark model and hence the development, in 1973, of the theory of Quantum Chromodynamics (QCD), which discussed quarks, hadrons, and their strong interactions. In combination with the electroweak theory, the QCD generated the standard model of particle physics. In 1969 Kendall helped found the Union of Concerned Scientists (UCS), a group charged with questioning the roles of technologies wrought by modern science, especially those related to defense systems (e.g., the “Star Wars” and B-2 [“Stealth”] bomber programs) and environmental issues such as the enhanced greenhouse effect. He became chairman of the UCS in 1973. In addition to his scientific and philanthropic interests, Kendall nurtured an adventuresome spirit, taking part in mountaineering expeditions to the Himalayas, the Arctic, and the Andes Mountains. He died while on an underwater photography session at Wakulla Springs State Park, Fla., where he was assisting a diving team from National Geographic magazine. Kendall received the Leo Szilard Award (of the American Physical Society) in 1981, the Bertrand Russell Society Award in 1982, and the Panofsky Prize in 1989.

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▪ American physicist

born Dec. 9, 1926, Boston, Mass., U.S.

died Feb. 15, 1999, Wakulla Springs State Park, Fla.

      American nuclear physicist who shared the 1990 Nobel Prize for Physics with Jerome Isaac Friedman (Friedman, Jerome Isaac) and Richard E. Taylor (Taylor, Richard E.) for obtaining experimental evidence for the existence of the subatomic particles known as quarks (quark).

      Kendall received his B.A. from Amherst College in 1950 and his Ph.D. from the Massachusetts Institute of Technology (MIT) in 1955. After serving as a U.S. National Science Foundation Fellow at MIT, he taught and pursued research at Stanford University (1956–61). In 1961 he joined the faculty of MIT, becoming a full professor in 1967.

      Kendall and his colleagues were cited by the Nobel committee for their “breakthrough in our understanding of matter” achieved while working together at the Stanford Linear Accelerator Center from 1967 to 1973. There they used a particle accelerator to direct a beam of high-energy electrons (electron) at target protons (proton) and neutrons (neutron). The way in which the electrons scattered from the targets indicated that the protons and neutrons were not the solid, uniformly dense bodies to be expected if they were truly fundamental particles, but were instead composed of still smaller particles. This confirmed the existence of the quarks that were first hypothesized (independently) in 1964 by Murray Gell-Mann (Gell-Mann, Murray) at the California Institute of Technology and by George Zweig. Kendall also did research in nuclear structure, in high-energy electron scattering, and in meson and neutrino physics.

      In addition to his scientific research, Kendall worked extensively with a variety of groups concerning the proper role and uses of science in society. He was a founder (1969) of the Union of Concerned Scientists and served as the group's chairman from 1973. Kendall also worked as a consultant on defense for the U.S. government for many years and was one of the scientists who briefed U.S. President Bill Clinton in 1997 on the problems that might be encountered should significant global warming occur. Some of Kendall's writings about his societal concerns include Energy Strategies—Toward a Solar Future (1980), Beyond the Freeze: The Road to Nuclear Sanity (1982), and The Fallacy of Star Wars (1984).

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