Andrew M. Sessler
University of California, Berkeley
December 11, 1928 - April 17, 2014
Election Year: 1990
Scientific Discipline: Physics
Membership Type: Member
Andrew M. Sessler was internationally known for his many contributions to accelerator and particle-beam physics. Without the base of knowledge he established, the storage rings, high-energy colliders, and synchrotron light sources vital to so many scientific discoveries would not have been possible. Sessler was also an outstanding leader of the U.S. physical science research community; among numerous other achievements, he helped transform the energy research landscape toward sustainable energy and global environmental protection. His leadership was critical not only in science per se. Sessler tirelessly pushed for freedom of scientific inquiry and the betterment of humankind, and he was an advocate for scientists’ rights worldwide. He was particularly proud of the role he played in arms control and especially in emphasizing the futility of antimissile defense.
Born and raised in New York City, Sessler attended college at Harvard University, where he majored in mathematics. He did his graduate studies, in physics, at Columbia University. After receiving his Ph.D., Sessler was in the first group of National Science Foundation postdocs; he worked at Cornell University with Hans Bethe. From 1954 to 1959 Sessler was on a faculty member of Ohio State University, after which he joined the Lawrence Radiation Laboratory, now the Lawrence Berkeley National Laboratory. He spent the rest of his career there and served as the laboratory’s director from 1973 to 1980.
Sessler was known for his “Jeffersonian science”—that is, research that has a defined long-term goal, as opposed “curiosity-based” scientific research. Thus although his efforts on radio-frequency manipulation of particles and the understanding of beam instabilities were basic science, they were needed for the development of colliders. Similarly, his work on optical guiding and beam conditioning was done to improve the performance of free electron lasers.