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Larmor precession is important in nuclear magnetic resonance, magnetic resonance imaging, electron paramagnetic resonance, muon spin resonance, and neutron spin echo. It is also important for the alignment of cosmic dust grains, which is a cause of the polarization of starlight .
one, B 0, is constant in time, the other one, ΔB z (t), may be time dependent. It is present in magnetic resonance imaging and helps with the spatial decoding of the NMR signal. M(t) × B(t) is the cross product of these two vectors. M 0 is the steady state nuclear magnetization (that is, for example, when t → ∞); it is in the z direction.
The neutron's gyromagnetic ratio is γ n = −1.832 471 74 (43) × 10 8 s −1 ⋅T −1. [37] The proton's gyromagnetic ratio is γ p = 2.675 221 8708 (11) × 10 8 s −1 ⋅T −1 . [ 38 ] The gyromagnetic ratio is also the ratio between the observed angular frequency of Larmor precession and the strength of the magnetic field in nuclear ...
Ferromagnetic resonance was experimentally discovered by V. K. Arkad'yev when he observed the absorption of UHF radiation by ferromagnetic materials in 1911. A qualitative explanation of FMR along with an explanation of the results from Arkad'yev was offered up by Ya. G. Dorfman in 1923, when he suggested that the optical transitions due to Zeeman splitting could provide a way to study ...
For example, phenomena in the microscopic domain that can to some extent be described by classical analogy are not really quantum phenomena. Since the basic elements of magnetic resonance have no classical origin, although analogy can be made with classical Larmor precession, MR should be treated as a quantum phenomenon.
Atoms after passing the first inhomogeneous field will split into 2 beams corresponding the spin up and spin down state. Select one beam (spin up state, for example) and let it pass the rotating field. If the rotating field has frequency (ω) equal to the Larmor frequency, it will produce a high intensity of the other beam (spin down state).
The spin–orbit potential consists of two parts. The Larmor part is connected to the interaction of the spin magnetic moment of the electron with the magnetic field of the nucleus in the co-moving frame of the electron. The second contribution is related to Thomas precession.
According to the shell model, protons or neutrons tend to form pairs of opposite total angular momentum.Therefore, the magnetic moment of a nucleus with even numbers of each protons and neutrons is zero, while that of a nucleus with an odd number of protons and even number of neutrons (or vice versa) will have to be that of the remaining unpaired nucleon.