Carroll W. Zabel, 87, died April 18, 2008, at his home in Boulder.

He was born Oct. 5, 1920, in Deer Creek, Minn.

Carroll earned a PhD in physics at the Massachusetts Institute of Technology in Cambridge, Mass.

During World War II, he worked at the MIT Radiation Laboratory, where he and his colleagues made fundamental contributions to the design and deployment of microwave radar systems. After the war, he was recruited by Los Alamos Scientific Laboratory in New Mexico, where he was involved in nuclear reactor research, in administration, and in consulting from 1949 to 1964.

Carroll accepted a professorship of physics at the University of Houston in Houston in 1964. While working in Texas, Carroll and his family spent summers at their cabin near Crested Butte.

He retired to Boulder, where he and his wife have lived since 1984. Carroll was known for his generosity, humor, love, respect, honesty, and the joy of family.

He loved being outdoors and with his family enjoyed skiing, hiking, and other outdoor activities in the mountains of northern New Mexico and Colorado.

Carroll is survived by his wife of 65 years, Grace; children Ellen Seale (Peter) Durst of Denver, Barbara (Tom Couser) Zabel and of Quaker Hill, Conn., and Garry (Thelma) Zabel of Glenwood Springs; grandchildren, Jennifer (Lalit) Bajaj of Denver, Geoffrey (Anda) of Denver, Amber (Ryan) French of Seattle, and Andrew Zabel of Seattle; and four great-grandchildren.

Donations in his honor can be made to Hospice Care of Boulder County (303-604-5235).