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arXiv · 1703.09972

Chirp Excitation

Navin Khaneja
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Abstract

The paper describes the design of broadband chirp excitation pulses in NMR. We first develop a three stage model for understanding chirp excitation in NMR. We then show how a chirp $\pi$ pulse can be used to refocus the phase of the chirp excitation pulse. The resulting magnetization still has some phase dispersion in it. We show how a combination of two chirp $\pi$ pulses instead of one can be used to eliminate this dispersion, leaving behind a small residual phase dispersion. The excitation pulse sequence presented here allow exciting arbitrary large bandwidths without increasing the peak rf-amplitude. Although methods presented in this paper have appeared elsewhere, we present complete analytical treatment that elucidates the working of these methods.

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Navin Khaneja. 2017-03-29. Chirp Excitation. https://doi.org/10.1016/j.jmr.2017.07.003

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