Figure 9.
Example of coil response correction for a 3He image of a cylindrical cell (with a small side stem) obtained at B0 = 3.9 mT, Larmor frequency of 127 kHz, and using a tuned receive coil with Q ~100. This results in a coil response with a width ~1.5 kHz across the image space. The acquired spectral width ~16.67 kHz. a) Raw image. b) Coil response function, expanded to the frequency range of the cropped FOV image shown in a). The profile was acquired with a single RF pulse and dead time <100 μs before the sample was placed in the coil. c) Corrected image obtained after each row of the raw image was divided by the response function below it. This image has a uniform signal intensity across the cell and a flat noise floor. Image acquisition parameters are the same as for Figure 8.