pulse sequence

File:MRI 2DFT SE PulseSequence.png pulse sequence.]]

File:Noesy pulse sequence.png

File:INEPT Pulse Sequence.png NMR pulse sequence for a heteronuclear experiment. The thin bar denotes a 90° pulse, while the thick bar denotes a 180° pulse. INEPT is a common building block of NMR experiments to improve ¹⁵N signal.{{cite book| author=M H Levitt| title=Spin Dynamics|publisher=John Wiley & Sons Ltd| date=2008 | isbn = 978-0470511176}}]]

In Fourier transform NMR spectroscopy and imaging, a pulse sequence describes a series of radio frequency pulses applied to the sample, such that the free induction decay is related to the characteristic frequencies of the desired signals. After applying a Fourier transform, the signal can be represented in the frequency domain as the NMR spectrum. In magnetic resonance imaging, additional gradient pulses are applied by switching magnetic fields that exhibit a space-dependent gradient which can be used to reconstruct spatially resolved images after applying Fourier transforms.{{cite book

| author = Bernstein, M.A.

| author2 = King, K.E.

| author3 = Zhou, X.J.

| author4 = Fong, W.

| date = 2004

| title = Handbook of MRI Pulse Sequences

| url = http://www.science-direct.com/science/book/9780120928613

| accessdate = 2008-04-08

}}

The outcome of pulse sequences is often analyzed using the product operator formalism.