ADIABATIC PULSES

Adiabatic pulses are sometimes considered to be mysterious and exotic entities which are difficult to understand, complex to generate and im practical to implement, This work is an attempt to bring familiarity a nd to fulfill the preliminary needs of anyone interested in learning m ore about this subject, The response of magnetization to stimuli produ ced by adiabatic pulses is analyzed using vector representations in a frequency modulated rotating frame, The first section deals with basic principles of amplitude and frequency modulated pulses and a vector r epresentation in a second rotating frame is used to explain how the ad iabatic condition can be satisfied. The subsequent section explains th e principles of offset independent adiabaticity, These principles are then used to design optimal functions for the amplitude, frequency, an d magnetic field gradient modulations for adiabatic inversion pulses, The last section considers some practical aspects for those who want t o develop methodologies involving adiabatic pulses, (C) 1997 John Wile y & Sons, Ltd.