In an underground laboratory, encased in concrete walls 8 feet thick, University of Maryland professor Victor Viola aims a stream of helium atoms traveling at nearly half the speed of light at an obscure metal called Lithium 7.

In the same laboratory, Dr. George Harrison of the University's medical school bombards tiny bean sprouts with high-velocity neutron beams, while another professor is using the equipment to pry open an infinitesimally small atom to observe the makeup of the nucleus.

Their common laboratory is the University of Maryland's "Sector-focused Ischronous Cyclotron," buried two stories underground beneath the Unversity's physics building in College Park, which is described as one of the largest and most sophisticated cyclotrons in the world.

Since its installation eight years ago at a cost of $4.3 million, scholars, physicists and astronomers have carried on man's ageless struggle to unlock the secrets of the universe in a series of complex experiments involving a process of splitting, breaking or fracturing the nuclei of atoms.

"What we are doing," says Prof. Harry Holmgren, who directs the cyclotron operation, "are the basic studies which are extending our understanding of the nature of matter. We must understand matter if we are going to be able to use it."

The equipment has enabled Viola to conduct experiments with the helium beam and Lithium 7 that he says tend to support a theory that argues that the universe was created billions of years ago in a huge, primal explosion. At the same time, through use of the neutron beam, Dr. Harrison hopes to discover a superior way to treat cancer.

In simplified terms, the cyclotron works by forcing atoms of helium or hydrogen through an electromagnetic field that hurls them faster and faster in an upwardly spiralling orbit.

Eventually the atoms reach speeds of one-quarter to one-half the speed of light - or 90,000 miles a second.

Reaching the upper rim of the spiral, the beam is deflected into a 4-inch diameter vacuum tube that shoots the particles directly at their target.

As the particles slam into the target - for example, a thin sheet of lead foil if the target is the nuclei of lead atoms - the protons and neutrons of the nuclei are knocked around like billiard balls. Radiation detectors monitor these collitions and a computer receives these reports and records them on tape.

"We are trying to learn something about matter distribution the surface of the nucleus of the atom," Holmgren said.

By measuring the kinds of collisions within the nuclei, the angles at which particles rebound when they collide, and what happens when a particle is knocked out of a nucleus, scientists add to their knowledge of the relationship of particles to each other, their distribution and the shape of various nuclei, Holmgren says.

When the cyclotron is running, he said, the radiation levels in the room where it is located are so intense that no one could survive for more than a few minutes - thus the 8-foot thick concrete walls.

So, when someone like Victor Viola wants to conduct his tests for Lithium 7, the operation is monitored two stories above at a huge instrument panel with a battery of screens and dials.

When he began his lithium experiments, Viola said, he was not necessarily looking for evidence to support or contradict any theories of creation. He was merely looking for the origins of Lithium 7 along with three other light metals.

To do that, the cyclotron was set up to duplicate the kinds to nuclear reactions that occur in the interstellar dust that fills vast expanse of space between the stars.

"What we're doing is using the cyclotron to duplicate the cosmic ray flox," said Viola. To do that, the cyclotron was set up to slam the nuclei of helium atoms into each other, bomboard carbon and nitrogen nuclei with protons, and trigger other nuclear reactions that resemble the cosmic ray process.

What the experiments showed was that the natural abundance of three of the metals could easily be explained by the cosmic ray process. "But every place where we have Lithium 7 invovled, the story breaks down," said Viola. "One has to find another source for the origin of Lithium 7 other than the nuclear reactions in the intersetellar dust."

Most physicists believe this points to the "big bang" as the source of most of the Lithium in the universe, he said.

While Viola continues his probe into the mysteries of Lithium 7, the Medical School's, Dr. Harrison searches for a better cure for cancer as he experiments with radiation treatment on bean sprouts.

"You can always eradicate a tumor with radiation, says Harrison, "but you run the risk of damaging the healthy cells, too. What we're looking for is a quality of radiation where the normal tissue can be spared."

There is evidence, Harrison said, that neutrons - those particles of the atomic nucleus that are not electrically charged - tend to attack the cancerous cells while leaving the healthy ones alone.

So, once every three or four months for the few years, Harrison has been loading a glass water tank filled with bean sprouts into the back seat of his car and driving from his Baltimore office to the cyclotron in College Park.

There he puts the sprouts directly in the path of a high velocity beam of neutrons being fired out of the cyclotron. He uses bean sprouts, Harrison says, because their radiation damage properties closely resemble those of human cells. He places them in a tank of water because that enchances their similarity to cells in the human body.

To produce neutron beams, Harrison uses deuterium gas, whose atomic nuclei consist of one neutron and one proton loosely bound together. These nuclei are slammed by the cyclotron into a shield of beryllium, a light metal whose nucleus has an extra, or spare, neutron.

Because the protons are electrically charged, they are stopped by the beryllium shield, but the neutrons break off and join with the extra beryllium neutron, producing the neutron beam.

Harrison figures he has subjected about 2,000 bean sprouts to the neutron treatment so far. He is convinced the cancer treatment is effective, but he is not yet sure just how effective.