Abstract

Progress in magnetic resonance imaging often relies on optimal design of radiofrequency pulses. Here, a flexible optimal control model based on the Bloch equations is introduced taking into account the main technical restrictions of a MR scanner hardware. An optimization method based on a combined semismooth Newton/quasi-Newton method, penalty methods and trust-region globalization is built. The method is extended to time-optimal control for designing minimum-duration RF pulses. The methods are tested in realistic numerical experiments.