Lamb–Mössbauer factor

In physics, the Lamb–Mössbauer factor (LMF, after Willis Lamb and Rudolf Mössbauer) or elastic incoherent structure factor (EISF) is the ratio of elastic to total incoherent neutron scattering, or the ratio of recoil-free to total nuclear resonant absorption in Mössbauer spectroscopy. The corresponding factor for coherent neutron or X-ray scattering is the Debye–Waller factor; often, that term is used in a more generic way to include the incoherent case as well.

When first reporting on recoil-free resonance absorption, Mössbauer (1959)^[1] cited relevant theoretical work by Lamb (1939).^[2] The first use of the term "Mössbauer–Lamb factor" seems to be by Tzara (1961);^[3] from 1962 on, the form "Lamb–Mössbauer factor" came into widespread use.

Singwi and Sjölander (1960)^[4] pointed out the close relation to incoherent neutron scattering. With the invention of backscattering spectrometers ,^[5] it became possible to measure the Lamb–Mössbauer factor as a function of the wavenumber (whereas Mössbauer spectroscopy operates at a fixed wavenumber). Subsequently, the term elastic incoherent structure factor became more frequent.

References

1. ^ Mössbauer, R. L. (1958), "Kernresonanzabsorption von Gammastrahlung in Ir¹⁹¹", Naturwissenschaften 45: 538–539, Bibcode 1958NW.....45..538M, doi:10.1007/BF00632050  (German)
2. ^ Lamb, W. E. (1939), "Capture of Neutrons by Atoms in a Crystal", Physical Review 55: 190–197, Bibcode 1939PhRv...55..190L, doi:10.1103/PhysRev.55.190 
3. ^ Tzara, C. (1961), "Diffusion des photons sur les atomes et les noyaux dans les cristaux", Journal de Physique et le Radium 22: 303–307, doi:10.1051/jphysrad:01961002205030300  (French)
4. ^ Swingi, K.; Sjölander, A. (1960), "Resonance Absorption of Nuclear Gamma Rays and the Dynamics of Atomic Motions", Physical Review 120: 1093, Bibcode 1960PhRv..120.1093S, doi:10.1103/PhysRev.120.1093 
5. ^ Alefeld, B.; Birr, M.; Heidemann, A. (1969), "Ein neues hochauflösendes Neutronenkristallspektrometer und seine Anwendung", Naturwissenschaften 56: 410, Bibcode 1969NW.....56..410A, doi:10.1007/BF00593617  (German)