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- Spin_echo abstract "In magnetic resonance, a spin echo is the refocusing of spin magnetisation by a pulse of resonant electromagnetic radiation. Modern nuclear magnetic resonance and magnetic resonance imaging make use of this effect.The NMR signal observed following an initial excitation pulse decays with time due to both spin relaxation and any inhomogeneous effects which cause different spins in the sample to precess at different rates. The first of these, relaxation, leads to an irreversible loss of magnetisation. However, the inhomogeneous dephasing can be removed by applying a 180° inversion pulse that inverts the magnetisation vectors. Examples of inhomogeneous effects include a magnetic field gradient and a distribution of chemical shifts. If the inversion pulse is applied after a period t of dephasing, the inhomogeneous evolution will rephase to form an echo at time 2t. In simple cases, the intensity of the echo relative to the initial signal is given by e-2t/T2 where T2 is the time constant for spin-spin relaxation. Echo phenomena are important features of coherent spectroscopy which have been used in fields other than magnetic resonance including laser spectroscopy and neutron scattering. Echoes were first detected in nuclear magnetic resonance by Erwin Hahn in 1950, and spin echoes are sometimes referred to as Hahn echoes. In nuclear magnetic resonance and magnetic resonance imaging, radiofrequency radiation is most commonly used.".
- Spin_echo thumbnail HahnEcho_GWM.gif?width=300.
- Spin_echo wikiPageExternalLink 872879.
- Spin_echo wikiPageExternalLink index.php?option=com_content&view=category&layout=blog&id=103&Itemid=271.
- Spin_echo wikiPageID "7937743".
- Spin_echo wikiPageRevisionID "540781314".
- Spin_echo hasPhotoCollection Spin_echo.
- Spin_echo subject Category:Magnetic_resonance_imaging.
- Spin_echo subject Category:Nuclear_magnetic_resonance.
- Spin_echo subject Category:Quantum_mechanics.
- Spin_echo subject Category:Scientific_techniques.
- Spin_echo subject Category:Spectroscopy.
- Spin_echo type Ability105616246.
- Spin_echo type Abstraction100002137.
- Spin_echo type Cognition100023271.
- Spin_echo type Know-how105616786.
- Spin_echo type Method105660268.
- Spin_echo type PsychologicalFeature100023100.
- Spin_echo type ScientificTechniques.
- Spin_echo type Technique105665146.
- Spin_echo comment "In magnetic resonance, a spin echo is the refocusing of spin magnetisation by a pulse of resonant electromagnetic radiation. Modern nuclear magnetic resonance and magnetic resonance imaging make use of this effect.The NMR signal observed following an initial excitation pulse decays with time due to both spin relaxation and any inhomogeneous effects which cause different spins in the sample to precess at different rates.".
- Spin_echo label "Eco de espín".
- Spin_echo label "Spin echo".
- Spin_echo label "Spin-Echo".
- Spin_echo label "Спиновое эхо".
- Spin_echo label "スピンエコー法".
- Spin_echo label "自旋迴訊".
- Spin_echo sameAs Spinové_echo.
- Spin_echo sameAs Spin-Echo.
- Spin_echo sameAs Eco_de_espín.
- Spin_echo sameAs スピンエコー法.
- Spin_echo sameAs m.026ks38.
- Spin_echo sameAs Q904043.
- Spin_echo sameAs Q904043.
- Spin_echo sameAs Spin_echo.
- Spin_echo wasDerivedFrom Spin_echo?oldid=540781314.
- Spin_echo depiction HahnEcho_GWM.gif.
- Spin_echo isPrimaryTopicOf Spin_echo.
