isomer shift

physics

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Last updated

June 29, 2026

Quick Summary

The isomer shift in physics refers to a change in the energy of a nuclear gamma ray. This shift occurs due to the electrostatic interaction between the nucleus's charge and the surrounding electrons' charge.1

This phenomenon provides a way to measure how the nuclear charge radius changes when a nucleus is in an excited state. It is a key concept within the broader field of the Mössbauer effect, which utilizes the resonance absorption of gamma rays to study various scientific phenomena. The isomer shift is distinct from other spectral shifts, such as the Doppler shift, which relates to the motion of the source or absorber.1

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Mössbauer effect
Applications
The isomer shift, the change in the energy of a nuclear gamma ray due to the electrostatic interaction between nuclear and electronic charge, provides a measurement of the change in the nuclear-charge radius when the nucleus is raised to an excited state. The splitting of nuclear…
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The isomer shift, the change in the energy of a nuclear gamma ray due to the electrostatic interaction between nuclear and electronic charge, provides a measurement of the change in the nuclear-charge radius when the nucleus is raised to an excited state. The splitting of nuclear…
Read More