precession


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Related to precession: precession of the equinoxes

precession

[-sesh′ən]
Etymology: L, praecedere, to go before
a comparatively slow gyration of the axis of a spinning body such that the axis traces out a cone, caused by the application of a torque. The magnetic moment of a nucleus with spin experiences such a torque when inclined at an angle to an applied magnetic field, resulting in precession at the Larmor frequency.

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 present discrepancies in the subcritical visibilities suggest there exists some cause of additional precession phase distribution broadening in the tunnelling transmission not considered in the present simulations and induced the measured visibility decrease after the superpositions over the phase distributions in the measuring process.
Prior to that time, the ice ages were governed by the regular Milankovitch factors of orbital tilt and precession.
The precession cycle would take just a matter of seconds or less to complete.
Like the Boulder group, Fortson's team observes the precession of atomic nuclei, but they're looking at mercury atoms at a much lower frequency (1 hertz).
Both Earth and a top are like gyroscopes, and anyone who plays with a gyroscope soon discovers that the direction of precession reverses with the direction of an external torque you apply.
To calculate what the precession should be, Guinan and Maloney calculated the amount predicted by classical (Newtonian) theory as 1.
Tenders are invited for Supply and commissioning of total field proton precession magnetometer with accessories and software
Precession is the final product of five years of work by Simon Cullen and Sorca McGrath who together form Ships.
The 21,000-year cycle involves precession, which is the change in the orientation of Earth's tilted rotational axis and what generates the temperature changes on Earth we call seasons.
Based on what the precession would have to be to explain the timing of previous outbursts, the team successfully predicted OJ 287's December 2015 flare.
One has to take into consideration that magnetic moment acts like a top, and, in non-relativistic case, precession of the nucleus is simple Larmor precession.
This entry-level, self-contained instrument is a non-slaved--you need to manually adjust for periodic gyro precession just as you would a plain-vanilla DG--vacuum-driven model that's found in various versions that all share the same basic operating logic.