论文信息 - Threshold voltages for hyperbolic secant inversion pulses

Threshold voltages for hyperbolic secant inversion pulses

Spin inversion produced by hyperbolic secant RF pulses is independent of pulse amplitude once a threshold value is exceeded. A semi‐empirical formula for these pulses has been derived by application of analytical solutions to the Bloch equations. This predicts the required coil voltages for inversion as a function of inversion bandwidth and side‐to‐width parameter μ, based on knowledge of a reference voltage for the loaded coil. The voltage required is shown to increase linearly with bandwidth but to fall with the μ, approximately as (1/μ)0·4. Experimental confirmation is presented, and factors affecting choice of pulse parameters are discussed.

M. Leach | G. Payne | M. Leach

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