I was reading a paper on hyphenating a gas chromatograph with an NMR. The authors describe a proof-of-concept type instrument. We have a couple of NMR experts here in SE, hoping to get some insight. The GC-NMR output is a plot of retention time (y-axis) vs. chemical shift (on the x-axis).
I wanted to confirm the meaning of the term "transient" as used in the figure caption of the following paper. The figure, taken from Analytical Chemistry (paper-behind paywall), shows how a GC is coupled to an NMR.
"Data acquisition parameters: 32 transients with 4k time domain points and a spectral width of 5618 Hz were accumulated with a relaxation delay of 500 ms."
Is transient just jargon for free induction decay signal? The complete term could be a transient signal/response. Also, if I understand correctly, 4k means that 4000 data points were collected in the FID after the NMR pulse, and the FID collection was delayed for 500 ms. I gather this "transient" wording is borrowed from electronics, where it refers to a quick change in the current in a circuit.
How does one control the spectral width of observation during data acquisition, say, as in this figure, it is 5168 Hz?
Acquisition time of 28 s (of FIDs or transients?). This time seems too long. Is this reasonable?
Article in question: Grynbaum, M. D.; Kreidler, D.; Rehbein, J.; Purea, A.; Schuler, P.; Schaal, W.; Czesla, H.; Webb, A.; Schurig, V.; Albert K. Hyphenation of Gas Chromatography to Microcoil $\ce{^1H}$ Nuclear Magnetic Resonance Spectroscopy in Anal. Chem. 2007, 79, 2708-2713; doi 10.1021/ac0617767.