In 1939, Ernest Lawrence (8/8/01 – 8/27/58) won the 1939 Nobel Prize in Physics for inventing the first cyclotron in 1934. The device is a specific type of particle accelerator. It is designed to hold charged subatomic particles along a curved path and introduce energy to increase their speed.

When the particles are accelerating rapidly enough around the inside perimeter, a slot at the rim is opened. The particles are shot out toward a target, which can be made of any number of materials. When they collide with the target material, they generate nuclear reactions. These create secondary particles, which can be analyzed.

The cyclotron, colloquially called an “atom smasher,” was replaced in the 1950’s by more advanced devices called synchrotrons. Today’s most powerful particle accelerator, a conceptual descendant of the cyclotron, is the Large Hadron Collider at CERN, in Switzerland

Cyclotrons are still used to generate particle beams for research and use in nuclear medicine. More than 1,200 cyclotrons are used, around the world, to produce radionuclides (or radioisotopes). These are used as biological and environmental tracers and for medical diagnosis and treatment. PET (positron emission tomography) scanning, for example, uses cyclotron-produced radioisotopes.

The image is of South Korea's RFT-30 cyclotron.

More Info: en.wikipedia.org