David Kolb, age 12, of Victoria, B.C., for his question:

What is a cyclotron?

The cyclotrcn is an age old dream come true. The alchemists of the Middle Ages wasted many hours trying to turn lead into gold. They called this the transmutation of matter. Later, when men learned more of chemistry they decided that this was impossible. Each element; they discovered, is made of atoms of a certain sort and an atom, they thought, could not be changed.    Then came the atom smashers who learned how to break atoms apart and even remake the pieces into different atoms.

With a cyclotron, our scientists can make gold from lead, though the process costs about 610,000 for each ounce of gold.  The rewards of the cyclotron, however, cannot be measured in gold. It is used to pry out the secrets of atoms, the tiny particles from which everything in the universe is made. With its help, several new elements have been discovered. It produces valuable radio active substances and it releases nuclear energy.

An atom is made of even smaller particles arid the nature of an atom depends upon the number of proton particles in its nucleus. The cyclotron uses atomic particles as bullets to break up the nuclei in the atoms of a target. The target is usually a thin, thin sheet of metal. The bullet particles are whipped to tremendous speeds and a few lucky ones will crash into atomic nuclei and cause their particles to be reshuffled. Nuclear energy is released in the process.

The mighty cyclotron is made from a vacuum chamber, a powerful magnetic field and a plentiful supply of electric power. The power is attached to two electrodes shaped in hollow half circles. The electrodes are called dees. Together they form a circle with a strip between them.

The electrodes are placed in the vacuum chamber and the chamber is set between two magnetic poles, which means that the parts axe in a magnetic field. The atomic bullets get their speed energy from a lot of little pushes. The pushes are given by spurts of electrical energy and aided by the energy of the magnetic field.

The atomic bullets start out in the strip between the two does. These electrodes prod them along with spurts of energy. The magnetic field keeps them traveling in a circle. The faster they travel, the wider the circle becomes. The electrodes vary their charges in step with the spreading bullets and, as the current changes, the bullets run downhill from one electrode to another. As they cross the center line, the opposite doe becomes downhill. With each trip they gain speed until at last the bullets are fast enough to be aimed at the target.