Obituary of Richard Yamamoto

Richard K. Yamamoto died October 16, 2009 at the age of 74 from complications related to lung cancer. Yamamoto, who was born and raised in Hawaii, entered MIT as a freshman in 1953 and spent his entire career at the Institute. He loved hands-on experimental work and contributing to advances in the understanding of elementary particles.

Yamamoto earned his bachelor’s and PhD degrees, both in physics, from MIT in 1957 and 1963, respectively. He joined MIT’s Laboratory for Nuclear Science in 1963 and became an instructor of physics in 1964. Joining the MIT faculty as an assistant professor in 1965, he then became a full professor in 1972.

Yamamoto’s career of particle physics research included experiments at Brookhaven, Fermilab, and SLAC. He worked early in his career at Brookhaven, and when the National Accelerator Laboratory, which became Fermilab, was created near Batavia, Illinois, he assumed a leading role in the creation, operation, and exploitation of the 30-inch Bubble Chamber Hybrid Spectrometer in studying hadronic interactions. Later, at SLAC he joined the SLD Collaboration, to study production and decay of Z0 bosons produced with polarized electron-positron collisions at the Stanford Linear Collider (SLC). Working on this experiment, he contributed to the most precise measurement of the electroweak mixing angle based on a polarized electron-positron scattering. This measurement remains an important constraint on models of electroweak symmetry breaking, including the possible mass of the Higgs Boson in the Standard Model. A key element of this work, in which Yamamoto’s group played a central role, was the precise measurement of the electron beam polarization based on Compton scattering.

Yamamoto’s research team also conducted precise studies of decays of charmed and bot- tom particles with the BaBar Collaboration at the SLAC B-factory. His group was heavily involved in the construction, calibration and operation of the BaBar drift chamber, a key component of the BaBar experiment, and contributed to the measurement of CP violation, and other important properties of the heavy mesons.

Yamamoto loved working with students both in the classroom and in the laboratory. He taught Junior Lab at MIT for many years and was a master of the all the experiments. He was happiest building something and making it work. Many of his students have gone on to careers in physics and carry with them his love of experimental hardware. Colleagues found him a pleasure to work with; his management was low-key, but quietly effective.

Yamamoto loved good Japanese food, was an excellent auto mechanic, and a devoted fan of fast cars. He was known for rebuilding his own car engines and enjoyed taking driving courses at NASCAR racetracks.

Yamamoto is survived by his wife, Kathleen Yamamoto; his former wife, Lily Yamamoto; three daughters, Cara-Jean Donaghey, Lani Yamamoto and Sharon Yamamoto; and eight grandchildren.