Hi,
Here is another study of me:
The
Larmor precession frequency is the rate of precession of a spin packet under the influence of a magnetic field. The frequency of an RF signal, which will cause a change in the nucleus spin energy level, is given by the Larmor equation. The frequency is determined by the gyro magnetic ratio of atoms and the strength of the magnetic field. The gyromagnetic ratio is different for each nucleus of different atoms.
The stronger the magnetic field, the higher the precessional frequency. If an RF pulse at the Larmor frequency is applied to the nucleus of an atom, the protons will alter their alignment from the direction of the main magnetic field to the direction opposite the main magnetic field. As the proton tries to realign with the main magnetic field, it will emit energy at the Larmor frequency. By varying the magnetic field across the body with a magnetic field gradient, the corresponding variation of the Larmor frequency can be used to encode the position. For protons (hydrogen nuclei), the Larmor frequency is 42.58 MHz/Tesla.
The
Larmor equation is important because it is the frequency at which the nucleus will absorb energy. The absorption of that energy will cause the proton to alter its alignment and ranges from 1-100 MHz in MRI. The equation states that the frequency of precession of the nuclear magnetic moment is directly proportional to the product of the magnetic field strength (B0) and the gyromagnetic ratio (g). This is stated mathematically as w= gB0.
NucleusThe core or center part of an atom, which contains protons having a positive charge and neutrons having no electrical charge, except in the common isotope of hydrogen, where the nucleus is a single proton.
Nuclei Unpaired Protons Unpaired Neutrons Net Spin (MHz/T)
1H 1 0 1/2 42.58
2H 1 1 1 6.54
Spin What is spin? Spin is a fundamental property of nature like electrical charge or mass. Spin comes in multiples of 1/2 and can be + or -. Protons, electrons, and neutrons possess spin. Individual unpaired electrons, protons, and neutrons each possesses a spin of 1/2.
Properties of SpinWhen placed in a magnetic field of strength B, a particle with a net spin can absorb a photon, of frequency V . The frequency depends on the gyromagnetic ratio, of the particle. For hydrogen, = 42.58 MHz / T. V=Y.B
http://www.cis.rit.edu/htbooks/nmr/chap-3/chap-3.htmbr
Steve
Ps. If any of you have an idea on how to build a test setup, please let me know.