Raymond Webster Hayward, a nuclear physicist and expert in the physics of beta decay in radionuclides, died following a heart attack on 24 December 2001 at his home in Bethesda, Maryland.
Ray was born on 28 July 1921 in Omaha, Nebraska. He received a BS in electrical engineering from Iowa State College in 1943. During World War II, he served in the US Navy and was stationed at the Naval Research Laboratory in Washington, DC. His work there involved putting connectors on cables, producing the wiring diagram for a captured Japanese fighter plane, and designing antennas.
Following his wartime service, he enrolled in graduate studies in physics at the University of California, Berkeley, where he received MA and PhD degrees in 1948 and 1950, respectively. His thesis work under A. Carl Helmholz dealt with construction of a beta-ray spectrometer and its use in studies of nuclear beta decay.
At Berkeley, he met the experimental physicist Evans Vaughan, who became his wife in 1947. Toward the end of their studies, around 1950, Emilio Segrè told her that Ugo Fano (see Physics Today, Physics Today 0031-9228 54 9 2001 73 https://doi.org/10.1063/1.1420522 September 2001, page 73 ) of the National Bureau of Standards in Washington, DC, had an opening suitable for Ray to implement an experimental program in beta spectrometry at NBS. As a result of this exchange, both Ray and Evans obtained positions at NBS.
In 1950, Ray joined Fano’s nuclear physics section at NBS (now known as the National Institute of Standards and Technology, or NIST) and began decay-scheme studies. Ray then moved to the radioactivity section under Wilfrid Mann and developed some of the first beta-gamma coincidence techniques for standardizing radionuclides used in nuclear medicine, such as iodine-131. In an article he wrote for Advances in Electronics in 1953, he gave a definitive description of the design and construction of beta-ray spectrometers.
In 1956, Ray became an adjunct professor of physics at the University of Maryland, College Park. When a separate nuclear spectrometry section was created at NBS during the mid-1960s, he was appointed its section chief.
Ray’s activities led to his participation, in 1956, in the famous fundamental experiment that demonstrated that parity is not conserved in weak interactions. Chien-Shiung Wu (see Physics Today, Physics Today 0031-9228 50 10 1997 120 https://doi.org/10.1063/1.2806727 October 1997, page 120 ) at Columbia University contacted Ernest Ambler in NBS’s cryogenic physics section, where one of us (Hudson) was chief, to suggest an experiment involving nonconservation of parity in the beta decay of cobalt-60 nuclei. Ray and his student Dale Hoppes helped design and construct the coincidence system. In 1962, Wu and the NBS team received the Franklin Institute’s John Price Wetherill Medal for this work. The Department of Commerce bestowed its Gold Medal on the NBS team in 1957.
With assistance from students at Maryland and the Catholic University of America, Ray further investigated correlations among nuclear spin, beta particles and subsequent gamma rays, and probed other fundamental characteristics of beta decay. He spent the year 1961–62 in Copenhagen at the Institute for Theoretical Physics (now known as the Niels Bohr Institute) for the stimulating experience of joining the community of Niels Bohr, his associates, and a transient complement of some 50 distinguished visitors. There, Ray engaged in lively discussions of the problems that, at that time, were at the forefront of nuclear and elementary particle physics. Ray then returned to NBS.
For the next 20 years, Ray delved into various aspects of theoretical physics, including the long-standing difficult problem of the dynamics of fields with intrinsic spin greater than one. In a comprehensive study in 1976 (NBS Monograph, number 154), he used the variational methods of classical Lagrangian field theory to develop a relativistic theory of higher-spin fields. Beginning in the late 1970s and continuing through the rest of his career, Ray studied gravitational wave detection; he focused in particular on performing quantum nondemolition experiments and examined in detail the quantum properties of the macroscopic harmonic oscillator. He discussed how to measure certain observables of a harmonic oscillator, without affecting the results of subsequent measurements of the oscillator, to a precision better than the uncertainty imposed by the quantum limit.
After Ray retired from NBS in 1980, he continued to study electromagnetism, quantum mechanics, relativity, weak interactions, and gravitation.
Ray was a courtly, affable man with a wry sense of humor. His hobbies included mountain climbing, hunting, and fly-fishing. He also enjoyed listening to classical music and owned an impressive collection of recordings. The Haywards regularly entertained physicists from all over the world and were famous for the large parties they held when meetings of the American Physical Society were scheduled in Washington, DC.
