Spin Echoes after ArbitraryNPulses

✍ Scribed by Mincheol Kim; Soonchil Lee

• Publisher: Elsevier Science
• Year: 1997
• Tongue: English
• Weight: 168 KB
• Volume: 125
• Category: Article
• ISSN: 1090-7807
• DOI: 10.1006/jmre.1996.1077

✦ Synopsis

Based on the Bloch equations, the general response of a nuclear by introducing the echo path concept. But there are many spin-1 2 system to multiple RF pulses with arbitrary phases and flip cases where the rotation axis is not fixed in a particular angles is presented. The general solution is expressed in a form direction. In the CPMG method (8) or the phase-cycling including the pathway vectors specifying the magnetization paths procedures (9, 10) devised to correct the schematic errors generated by a string of pulses. The pathway vectors are useful generated during data acquisition by the incompleteness of for predicting the exact positions, magnitudes, and number of an instrument, RF pulses of various phase angles are required echoes. Also, these vectors make it easy to trace the physical origin in the x-y plane. Besides, the rotation axis is not even in of an echo formation. It is shown that the maximum number of the x-y plane for the nuclei which are off resonance. Thereechoes after N pulses is (3 N 01 0 1)/2 using this concept. ᭧ 1997 fore, the application of the analyses of Kaiser et al. is re-

Academic Press

stricted.

In this work, we present the general solution of the Bloch equations for pulse sequences, where each pulse has arbitrary 114