Dr. Benson T. Chertok, 46, a professor of physics at American University who was known for his contributions in experimental and theoretical high energy nuclear physics, died of cancer Thursday at Georgetown University Hospital. He lived in Bethesda.

Dr. Chertok became a member of the physics department at American University in 1966. In the early 1970s, he headed an effort that performed a series of experiments using the high-energy electron beam at the Stanford Linear Accelerator Center.

This work helped establish a new area of research into the quark structure of nuclei. Quarks are subatomic particles believed to be the building blocks of protons and neutrons, the constituents of all nuclei.

Dr. Chertok recently returned from a sabbatical year at the Center for European Nuclear Research, where he was a member of a group studying high energy collisions between protons and anti-protons which have been accelerated to within 99.7 percent of the speed of light.

At American University, he developed a course called Arms Control, Politics and Science. It concerns the role of science in society.

Dr. Chertok was born in Laconia, N.H., earned a bachelor's degree and a master's degree in nuclear engineering from Massachusetts Institute of Technology and a doctorate in physics from Boston University. He also attended the University of Gottingen, Germany.

He was a captain in the Army Reserve and a member of the American Physical Society.

Survivors include his wife, the former Barbara Liss, a daughter, Victoria, and a son, Maxwell, all of Bethesda, and a brother, Edwin, of Laconia.

The family suggests that expressions of sympathy be in the form of contributions to the Benson T. Chertok Scholarship Fund, Office of University Development, The American University, Washington, D.C.