precession


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Related to precession: precession of the equinoxes

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 ?
Xu, "Modeling of wideband radar signature for precession space objects," Acta Electronica Sinica, Vol.
The precession geometry for a rotationally symmetric BT is shown in Fig.
Any deflection of the propeller out of its plane of rotation causes precession, so tricycle-gear airplanes also are affected.
Consequently, the equations by which there are determined the natural angular frequencies, regarding both the forward and backward precession, are obtained out of the relations (4), (6) by substituting h with -h.
The variation in brightness of DW UMa over the accretion disc precession period is shown in Figure 2.
The question about whether only the field component that rotated with precession or both field components were involved in generating an MRI image suddenly became a significant issue in equipment design, particularly in the design of the RF coils.
Observations of the precession of the millisecond pulsar PSR B1516+O2B, located some 25,000 light-years away in the globular cluster M5, indicate that the pulsar most likely has a mass equivalent to about 1.94 suns.
Precession is a common feature of spinning objects.
In what follows it will be proved that this date is 1911 June 22 and that Roelofs used the astronomical observations of Van Stockum from 1911 corrected for precession and nutation and published them in his book, Astronomy Applied to Land Surveying.
For his remaining twenty-four years he made big, labor-intensive paintings inspired by the Mayan calendrical system, Goethe's color theory, Faraday's electromagnetics, the precession of the equinoxes, the I Ching, Yuri Gagarin, you name it.
By varying the strength of an applied magnetic field, the frequency of the precession can be changed.
Sidharth provides incontrovertible evidence that such advanced "European" astronomical concepts as precession, heliocentrism, and eclipse cycle were first discovered and encoded in the ancient Indian texts, passages of which made perfect sense only if there astronomical keys are shown.