DONALD W. BARR May 6, 1932 – Feb. 23, 2020

Don Barr was born in Worcester, MA to Addison W. and Evelyn M. Barr on May 6, 1932.

After attending public schools he earned his B.S. in chemistry from the University of Massachusetts. He and Marilyn married in 1954 and moved to Berkeley, CA where Don embarked on a PhD program in radiochemistry at UC under Glenn Seaborg.

After completing his degree Don and Marilyn moved to Los Alamos where Don spent the rest of his career at LANL, achieving recognition for his research accomplishments as a lab fellow, and an E. O. Lawrence award winner. He served as Chemistry Division (INC) leader until retirement in 1989 when he and Marilyn moved to Jemez Springs.

As is often the case it was a retirement in name only as Don drove over the Jemez several days a week for the next quarter century as a LANL affiliate.

In the last few years, confined to a wheelchair he continued to bulldog issues of weapon yield estimation. Last summer he proudly shared his meticulously hand-drawn graph that demonstrated his position on a nuance of yield estimation that had occupied much of his career.

Don leaves his wife of 66 years, Marilyn, sons Jim and Glenn, daughters Sandy and Brenda and three grandchildren.