Rapid longitudinal relaxation measurement of hyperpolarized 129Xe by a highly sensitive atomic magnetometer

A fast and accurate determination of longitudinal relaxation time is put forward for hyperpolarized 129Xe. The theoretical framework for the method is developed. Measurement of the longitudinal relaxation time is by the determination of a close-loop response of 129Xe magnetization to the external magnetic fields and is implemented with a highly sensitive Rb magnetometer. The indirect measurement dramatically reduces the time consuming than the conventional inversion-recovery method and is more suitable for the samples with long longitudinal relaxation time.