Modelling and correcting the impact of RF pulses for continuous monitoring of hyperpolarized NMR.

ABSTRACT: Monitoring the build-up or decay of hyperpolarization in nuclear magnetic resonance requires radio-frequency (RF) pulses to generate observable nuclear magnetization. However, the pulses also lead to a depletion of the polarization and, thus, alter the spin dynamics. To simulate the effects of RF pulses on the polarization build-up and decay, we propose a first-order rate-equation model describing the dynamics of the hyperpolarization process through a single source and a relaxation term. The model offers a direct interpretation of the measured steady-state polarization and build-up time constant. Furthermore, the rate-equation model is used to study three different methods to correct the errors introduced by RF pulses: (i) a 1/cos⁡n-1θ correction (θ denoting the RF pulse flip angle), whic

SUBMITTER: von Witte G 

PROVIDER: S-EPMC10583294 | biostudies-literature | 2023

REPOSITORIES: biostudies-literature