Karl Brown, 76; Developer of Cancer Treatment Equipment
Karl L. Brown, a pioneer in the development of compact linear accelerators used in cancer treatment and the developer of a computer code used worldwide for spectrometers, beam lines and accelerators, died Aug. 29 of heart failure. He was 76.
More than 100,000 people around the globe are treated each day using the machines Brown helped create. They aim precise beams of radiation at tumors while minimizing exposure to surrounding healthy tissues.
Although Brown’s international reputation stemmed from his expertise in beam optics for nuclear spectrometers and high-energy particle accelerators, he was proudest of his work to aid cancer patients.
In the 1950s, Brown was part of a team of Stanford University researchers that designed the first linear accelerator in the United States used to treat a cancer patient, said Dr. Gregory Loew, deputy director of the Stanford Linear Accelerator Center.
Brown worked with Varian Associates over the next decade to develop the first commercial line of small accelerators for radiotherapy, called the Clinac series.
From 1966 to 1968, he took a leave from Stanford to serve full time as Varian’s research director, and remained a consultant after returning to the university.
Brown also was one of the first scientists to use matrix algebra for calculations involving charged particle spectrometers, which scientists use to analyze atomic particles. He designed a computer code called Transport that could manipulate the size and shape of a beam to ensure it would travel through Stanford’s 2-mile-long accelerator. The code became a basic international tool.
“His main contribution was to develop the scientific and mathematical concepts for magnetic-optical systems for charged particle transport,” said experimental physicist Vera Luth, Brown’s wife for 25 years, “and to make them widely accessible for practical use by scientists and engineers.”
During the early 1960s, Brown began using magnets with six poles, which improved the resolution of spectrometers at the Stanford accelerator’s terminus, where scientists experimented with beams of high-energy electrons that struck stationary atoms. The six-pole magnets now are used in many accelerators to keep particles tightly packed within beams.
Born in Coalville, Utah, Brown attended the University of Utah majoring in electrical engineering, but transferred to Stanford in 1946 to work on particle accelerators.
Except for sabbaticals to work for Varian and help design spectrometers and accelerators in Europe and Texas, he remained at Stanford for the rest of his life.
Brown earned his bachelor’s, master’s and doctorate degrees at the university, taught applied research there, and became a mainstay of the linear accelerator center he helped create.
In addition to his wife, Brown is survived by five children from his earlier marriage to Anadel Smith-Law and 14 grandchildren.
A memorial service is scheduled for 10 a.m. Friday at Valley Presbyterian Church in Portola Valley. The family has asked that, instead of flowers, donations be made to the Karl L. Brown Memorial Young Scholars Fund. Information about the fund is available on the Web site www.karlbrown.info.
