Robert Vose Langmuir; Caltech Physicist

Robert Vose Langmuir, 80, Caltech physicist who co-developed the original analytical mass spectrometer. Educated at Harvard and Caltech, Langmuir was working for Consolidated Engineering Corp. in Pasadena in 1939 when he and four others developed the spectrometer, which is used to identify the kinds of particles present in a substance. In 1940 he invented and patented a mass spectrometer, and later constructed the first synchrotron to operate in the United States. He also discovered the radioactive isotope K37. During World War II, Langmuir was a physicist at the General Electric Research Laboratories in Schenectady, N.Y., developing CW magnetrons, which were used by the Navy to jam enemy radar. From 1948 until his retirement in 1980, Langmuir taught and did research in physics and electrical engineering at Caltech. On May 1 in Altadena of cancer.