A cyclotron is a type of particle accelerator that uses a magnetic field and electric fields to accelerate charged particles, such as protons or ions, to high speeds. It consists of two hollow, D-shaped electrodes called "dees" placed in a vacuum chamber. When a charged particle is injected into the cyclotron, it spirals outward as it gains energy from the alternating electric field, eventually reaching significant velocities. Cyclotrons are commonly used in medical applications, particularly in the production of radioisotopes for PET scans and radiation therapy. They also play a role in scientific research, helping physicists study the properties of atomic nuclei and fundamental particles.