A synchrotron uses a cyclic particle accelerator to accelerate charged particles to very high energies using alternating electric and magnetic fields. The first electron synchrotron was constructed in 1945 by Edwin McMillan at the University of California, designed for energies between 320-350 MeV. A synchrotron consists of an electron gun, linear accelerator, booster ring, storage ring, beamline, and end station to produce and direct beams of synchrotron light for applications in spectroscopy, crystallography, medical imaging, and cancer therapy.