A National Science Foundation Advisory committee has recommended closing the University of Maryland's cyclotron, the prize research facility of the physics faculty at College Park.

At a time of declining federal support for research in atomic physics, the panel of physicists concluded, researchers should consolidate their facilities, rather than allowing all facilities to receive only partial funding.

The $16 million, 450-ton cyclotron at the University of Maryland was considered one of the largest and most sophisticated of its kind when it was opened in 1969.

"It would be an important loss. It's extremely important to us," said Robert Park, chairman of the physics department at College Park. "But we would not be out of the business of doing experimental nuclear physics."

"I'm not happy with the decision. I think we're doing good work and we should be funded," said Philip Roos, deputy director of the cyclotron group at College Park. The university receives $1 million in NSF funds annually to operate th cyclotron.

Built by the federal government, the cyclotron enables physicists and astronomers to carry on a series of complex experiments involving a process of splitting, breaking or fracturing the nuclei of atoms.

In simplified terms, it works by forcing atoms through an electromagnetic field that hurls them faster and faster in an upwardly spiraling orbit. When they reach speeds of 90,000 miles a second, they are deflected off the rim of the spiral and slammed into other atoms. The impact knocks the protons and neutrons of the nuclei around like billiard balls.

By studying this process, scientists are able to learn about the particles' relationships to each other.

In addition to the recommendation concerning the Maryland cyclotron, the panel also recommended closing one of the smaller nuclear accelerators at Stanford University in Californaia. Officials at Stanford said, however, they expected the decision and already had planned to phase out operations at that faciltiy.

The Stanford official also said the university has other accelerators, including the mile-long linear accelerator.

In recommending the shutoff of funds for Maryland, the NSF panel said it was not criticizing the quality of the work being done there. The panel urged that the Maryland faculty continue to receive funds to do research at other accelerators.

Maryland and Stanford were among 11 institutions whose nuclear accelerators were reviewed by the NSF panel. The panel concluded that by closing those two down, it could provide added support to the remaining nine.

"All of these laboratories are under-funded for optimum use. They [the panel] suggested that for optimized funding of some of the laboratories, that some be closed and others funded at maximum," said one Maryland physicist.

The Maryland cyclotron receives about $1 million a year in NSF funding plus some additional state grants. But Parks said loss of the NSF money would almost certainly result in closing of the cyclotron.

While the panel's recommendation is advisory, it nevertheless does carry weight, and Maryland physicists conceded that closure of the cyclotron is now a strong probability.

University Presdent John S. Toll, former chairman of the physics department at College Park and the man who built it into national prominence during the 1950s and '60s, was reported to be planning a major lobbying campaign against the closure. University officials predicted he will seek the help of the state's congressional delegation.