precession

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precession

An MRI term for the relatively slow gyration of the axis of a spinning body, which traces out a conical configuration. Precision is caused by the application of a torque which tends to change the direction of the rotation axis and is continuously directed at right angles to the plane of the torque. The magnetic moment of a nucleus with spin will experience such a torque when inclined at an angle to the magnetic field, resulting in precession at the Larmor frequency.

pre·ces·sion

(prē-sesh'ŭn)
The secondary spin of magnetic movements around the main magnetic field.
References in periodicals archive ?
The first time-resolved measurement of precessional dynamics in nanomagnet arrays induced by magnetic field pulse was reported by Kruglyak et al.
If [J.sub.rot] is directed outward from the supporting point, the dead weight would produce a torque equal in magnitude but opposite to the direction for [[tau].sub.pcn], which would cancel the precessional motion.
Now, the simulation of wideband radar echo of ballistic midcourse target with precession is mostly on the basis of ideal scattering centers, and the movement of these scattering centers is equaled to the precessional movement of the target.
LLG equation consists of three torques which are precessional torque, damping torque, and STT as shown in the following [5]:
These disadvantages do not occur in case of the precessional planetary transmission.
These speeds in turn are related to the precessional rate of the nuclei when subjected to the magnetic field.
precessional motion is likened to liberation or oscillation of the
Furthermore, when an RF pulse is applied to the nuclei in the magnetic field at a frequency that matches the precessional frequency of the nuclei, a condition known as resonance occurs.
It looked also at an earlier example of Mark's collaboration with a Philadelphia poet, Eleanor Wilner's Precessional (Wallingford, PA: 1998).
Built at NIST-Boulder, the CryoPIMM will be a powerful new tool to investigate the fundamental origins of precessional damping in thin metallic films.
Precessional switching requires a single polarity pulse applied to the device easy axis.
The reaction of the two particles also results in a precessional effect to the second particle (Resultant- in Figure 1).