Dr. Ranjbar completed his Ph.D. while working at Brookhaven National Laboratory (BNL) under the guidance of Dr. S. Y. Lee of Indiana University in Bloomington and Dr. Waldo MacKay of BNL. There his focus was on the AGS and RHIC polarized proton runs. Later he worked as a research associate in Fermilab's Accelerator Division in the Tevatron Department and the Accelerator physics department. During which time he developed several new applications important for the Tevatron's daily operation. These included a head-tail chromaticity measurement system and an orbit stabilization system.

As a result of this work he was awarded two letters of recognition from the Accelerator department head. In addition to operations work he has continued research in the areas of collective effects of beam motion, in particular chromatic and impedance extrapolation from measured transverse beam profiles. In addition he has been involved with work concerning beam-beam simulation codes for RHIC and the LHC. He currently works as a research scientist at Tech-X contributing to simulation work related to RHIC-II e-cooling upgrade project and the development of spin tracking codes.