The distribution associated with the magnitude of the noise amplitude following a Gaussian distribution. The mean value of this distribution is roughly 1.25 s0, where s0 is the standard deviation of the original Gaussian distribution.

The exchange of energy at a particular frequency between two systems; a large amplitude vibration in a mechanical or electrical system caused by a relatively small periodic stimulus with a frequency at or close to a natural frequency of the system.
Resonance is referred to as the property of an atom to absorb energy only at the Larmor frequency. The energy must also be delivered at 90° to the net magnetic vector (NMV) and main magnetic field (B0). Otherwise, no energy will be absorbed, resonance will not have occurred and an image cannot be created. In MRI systems, resonance can refer to the MR itself or to the tuning of the RF circuitry.

The time linearly from 0 to its maximum flat top measured in mT/m or G/cm. 10 mT/m=1G/cm. The height of the flat top influences the FOV. The higher the flat top or maximum gradient amplitude the smaller the FOV and the thinner the available slice thickness.

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Artifacts either by distorting the k-space trajectory (i.e. due to imperfect shimming) or as a consequence of the reduced bandwidth in the phase encode direction, commonly with EPI sequences.
While a standard spin warp-based sequence has an infinitely large bandwidth in the phase encode direction (about 1 or 2 kH), the bandwidth in EPI is related to the time between the gradient echoes (about a millisecond).
Hence even small frequency offsets can result in significant shifts of the signal in the phase encoding direction. Segmentation can introduce ghosting if there are significant difference in the amplitude and phase of the signal. This can be a particular problem when trying to acquire the segments in rapid succession.

Suitable choices of excitation schemes and/or subsequent correction can help to reduce this artifact. The signal from fat can easily be offset by a large fraction of the FOV, and must be suppressed. The effect of frequency offsets can be reduced by collecting data with more than one excitation, which effectively increases the bandwidth in the phase encoding direction.

From GE Healthcare;
the Signa Ovationâ„¢ is a patient-friendly open MRI scanner designed not only to handle a typical patient mix, but to accommodate larger patients, patients who are claustrophobic, and others who have difficulty tolerating the close quarters of conventional MR machines.