main photo of William J. Welch

William J. Welch

Professor Emeritus

Research Areas

  • Nano-Optoelectronics, Electromagnetics/Plasmas


William J. Welch received a B.S. in Physics from Stanford University in 1955, and the M.S. and Ph.D. degrees in Engineering Sciences from the University of California, Berkeley, in 1958 and 1960, respectively. He joined the faculty of the Electrical Engineering and Computer Sciences Department in 1960, and in 1971 became a faculty member of the Astronomy Department. Prof. Welch retired as Professor Emeritus in 2005 and is currently a Professor in the Graduate School. His specialty area is radio astronomy, with research focusing specifically upon the formation of stars, dark dust clouds, the Michelson interferometer array, and the Allen telescope array.

Considered one of the founders of molecular radio astronomy, Prof. Welch is the author or co-author of over 100 journal articles and conference papers. Elected to the National Academy of Sciences in 1999, his citation reads: "He started the field of millimeter-wave interferometry and remains one of its most active practitioners. His discoveries in star formation include the first hot cores associated with massive protostars and their subsequent evolution into ultracompact HII regions."

Prof. Welch was the director of the Radio Astronomy Lab at U.C. Berkeley from 1971-1996, and continues to participate in both the CARMA (Combined Array for Research in Millimeter-wave Astronomy) Project and the Allen Telescope Array Project, which is being conducted jointly with the SETI Institute. From 1998-2005, he held the Watson and Marilyn Alberts Chair in the Search for Extraterrestrial Intelligence, and is a member of the SETI Institute Board of Trustees.

Prof. Welch is a Fellow of the American Academy for the Advancement of Science; a member of the American Astronomical Society; a member of URSI, Commission V; and a member of the International Astronomical Union. He received a Docteur Honoris Causa from the Université de Bordeaux I in 1979. In 1996, he was a recipient of the Berkeley Citation in acknowledgment of his significant contributions to the field of radio astronomy and his distinguished service to the campus.

Selected Publications