In
physics, the
gyromagnetic ratio (also sometimes known as the
magnetogyric ratio in other disciplines) of a particle or system is the
ratio of its
magnetic dipole moment to its
angular momentum, and it is often denoted by the symbol
γ, gamma. Its
SI units are
radian per second per tesla (s<sup>−1</sup>·T<sup> -1</sup>) or, equivalently,
coulomb per kilogram (C·kg<sup>−1</sup>).
The term "gyromagnetic ratio" is sometimes usedFor example, see: D.C. Giancoli,
Physics for Scientists and Engineers, 3rd ed., page 1017. Or see: P.A. Tipler and R.A. Llewellyn,
Modern Physics, 4th ed., page 309. as a synonym for a
different but closely-related quantity, the
g-factor. The g-factor, unlike the gyromagnetic ratio, is
dimensionless. For more on the g-factor, see below, or see the article
g-factor.
Gyromagnetic ratio and Larmor precession
Any free system with a constant gyromagnetic ratio, such as a rigid system of charges, a
nucleus, or an
electron, when placed in an external
magnetic field B (measured in teslas) that is not aligned with its
magnetic moment, will
precess at a
frequency f (measured in
hertz), that is proportional to the external field:
- <math>f=fracB</math> .
For this reason, values of γ/(2π), in units of
hertz per tesla (Hz/T), are often quoted instead of γ.
This relationship also explains an apparent contradiction between the two equivalent terms,
gyromagnetic ratio versus......
Read More