Effect of distant dipolar field and T2 on magnetization in CRAZED-multiecho pulse sequence
Wong C, Zhong J, Kwok E
University of Rochester
It has been recently demonstrated that the finite duration of refocusing pulses in the multiecho acquisition of intermolecular double quantum coherence signal leads to significant signal attenuation. Here we explain such phenomenon by evaluating the effect of distant dipolar field and transverse relaxation T2 on the magnetization in a CRAZED-multiecho pulse sequence. The result demonstrates the signal rises primarily during the free evolution time in the acquisition period, and the siganl attenuation is proportional to the pulse duration. In addition, for a large range of T2, maximal SNR is obtained when the pulse duration is half of the pulse separation.