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NET MAGNETIZATION VECTOR
A vector which represents the sum of all of the contributions of the magnetic moments within the magnetic field; the magnitude and direction of the magnetization resulting from this collection of atomic nuclei.
NEUTRON
An uncharged neutral particle located in the nucleus of most atoms which serves as a stabilizer.
NEX
Number of excitations. See also Number of Excitations, Signal Averaging.
NMR SIGNAL
The electromagnetic signal in the radio-frequency range produced by the precession of the transverse magnetization of the spins. The rotation of the transverse magnetization induces a voltage in a receiving antenna (coil) which is amplified and demodulated by the receiver circuits.
NOISE
An undesirable background interference or disturbance that affects image quality. NSA - the number of signal averages performed during the scan. See also NEX and Signal Averaging.
NUCLEAR SPIN
Also known as inherent spin, this defines the intrinsic property of certain nuclei (those with odd numbers of protons and/or neutrons in their nucleus) to exhibit angular momentum and a magnetic moment. Nuclei that do not exhibit this characteristic will not produce an NMR signal.
NUCLEUS
The 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.
NUMBER OF EXCITATIONS
An indicator of how many times each line of k-space data is acquired during the scan.
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