Charles Thornton Murphy, who helped build Fermilab, died on 12 October 2001 of complications following a fall at his home in Batavia, Illinois.
C. Thornton Murphy, as he was commonly known, was born in Cambridge, Massachusetts, on 20 May 1938. The son of a classics professor, he traveled as a boy with his family throughout Europe. He eventually became fluent in Italian and French. In 1959, he graduated from Princeton University with a BA in physics. He earned an MS in 1961 and a PhD in 1964, both in physics, from the University of Wisconsin–Madison. His doctoral thesis, which addressed an experimental study of the branching ratios of the decay modes hadron(s), was prepared under the guidance of Jack Fry.
As a research associate at Wisconsin, he worked on bubble chamber physics at the Lawrence Berkeley Laboratory. He joined the University of Michigan as an assistant professor of physics in 1964, moving in 1968 to Carnegie Mellon University, where he developed several teaching innovations, including courses in relativity and new approaches to laboratory classes.
On his arrival at Fermilab in 1972, Murphy inaugurated a bubble chamber program. He then shifted his research focus to the development of beams and experimental facilities. He was an important contributor to the design and construction of the proton laboratory, one of the three major experimental areas at that time. In 1977, he became the head of the proton laboratory.
Murphy headed the research division’s beams group (1984–86), the cryogenic department (1986–88), and the research facilities department (1993–96). He played a key role in the Tevatron installation. An expert on the surveying requirements of large accelerator facilities, he consulted from 1991 to 1993 on the Superconducting Super Collider (SSC) project.
During his 28 years at Fermilab, Murphy continued the bubble chamber research he had begun at Michigan and Carnegie Mellon. He served as spokesman for the Fermilab bubble chamber experiment E-194, a study of proton interactions in deuterium. When that program was completed, he developed an interest in electronic experiments; that interest culminated in an extensive series of experiments on quark–antiquark and quark–gluon interactions that produced direct photons, muon pairs, charmonium states, and B mesons. The possibilities for using very-high-energy proton beams to produce large samples of B mesons led Murphy to combine his research and beams interests into an innovative proposal to extract a 20-TeV beam from the SSC using bent crystal channeling. In 1995, he then led a successful test of the process at the Tevatron. At the time of his death, Murphy was the manager of the Fermilab Switchyard 120 project that involved extracting the main-injector beam for fixed-target experiments.
Throughout his professional life, Murphy continued his interests in traveling and contacting scientists throughout the world. He developed an extensive network in Europe and Russia to support the SSC/Tevatron bent-crystal extraction test. He was a visiting scientist at CERN from 1985 to 1986, at the University of Hawaii at Manoa in 1991, and at the Frascati National Laboratories (LNF) in Italy from 1997 to 1998.
Murphy was fond of music. Only days before his accident, he led Fermilab in singing “Happy Birthday,” in both Italian and English, to celebrate the 100th anniversary of Enrico Fermi’s birth.