William Kraushaar, 87; studied gamma rays in Milky Way
William L. Kraushaar, a pioneer in the study of cosmic gamma rays and a former physics professor at MIT, died March 21 in Gorham, Maine, of complications from Parkinson's disease. A resident of Scarborough, Maine, he was 87.
Joining the Massachusetts Institute of Technology in 1949 as a research associate, Dr. Kraushaar devoted much of his career to the study of interstellar matter. At MIT in the mid-1950s, he began mapping out gamma rays, which are potent but invisible light waves.
Because his work could not be done from Earth or with high-altitude balloons, he used sounding rockets that broke through the atmosphere and gave researchers the first sense of the rays' origin.
In 1958, he proposed a gamma ray experiment on what would become known as Explorer 11, the first orbiting astronomical observatory. Launched in April 1961, it mapped gamma rays in the Milky Way galaxy, according to a statement from MIT.
"He was a pioneer," said Lynn R. Cominsky, chair of the astrophysics and astronomy department at Sonoma State University, told the Associated Press.
A subsequent experiment yielded the first definitive all-sky map of gamma rays from directions in the Milky Way where interactions of charged rays with interstellar matter were most abundant. The experiment also expanded the field of research beyond the Milky Way, discovering sources from the inside of distant galaxies. These sources have since been identified as giant black holes.
Dr. Kraushaar moved to the University of Wisconsin in 1965. There, he established a research group in X-ray astronomy whose work revealed a violent part of the universe, one that contained previously unsuspected black holes and million-degree gas.
A native of Maplewood, N.J., Dr. Kraushaar was a graduate of Lafayette College and received his doctorate from Cornell University. A Fulbright and Guggenheim fellow, he received the Alexander von Humboldt Senior US Scientist Award for a sabbatical year in 1983 at the Max Planck Institute for Astrophysics in Germany.
He was the author, in 1960, of the college physics textbook, "Introduction to Mechanics, Matter and Waves."
He moved to Scarborough after retirement in 1999.
Dr. Kraushaar leaves his wife, Elizabeth; three children from his first marriage, and three stepchildren.
Memorial services are planned April 16 in Madison, Wis., and May 4 in Portland, Maine. 