quasielastic scattering

In physics, quasielastic scattering designates a limiting case of inelastic scattering, characterized by energy transfers being small compared to the incident energy of the scattered particles.

The term was originally coined in nuclear physics.{{cite journal | last1=Chamberlain | first1=O. | last2=Segrè | first2=E. | last3=Tripp | first3=R. | last4=Wiegand | first4=C. | last5=Ypsilantis | first5=T. | title=Experiments with High-Energy Polarized Protons | journal=Physical Review | publisher=American Physical Society (APS) | volume=93 | issue=6 | date=1954-03-15 | issn=0031-899X | doi=10.1103/physrev.93.1430 | pages=1430–1431| url=https://escholarship.org/content/qt01d5k88d/qt01d5k88d.pdf?t=lnr1gg }}

It was applied to thermal neutron scattering by Leon van Hove{{cite journal | last1=Van Hove | first1=L. | last2=McVoy | first2=K.W. | title=Pair distribution functions and scattering phenomena | journal=Nuclear Physics | publisher=Elsevier BV | volume=33 | year=1962 | issn=0029-5582 | doi=10.1016/0029-5582(62)90539-4 | pages=468–476| url=https://cds.cern.ch/record/343802 }} and Pierre Gilles de Gennes{{cite journal | last=de Gennes | first=P.G. | title=Collective motions of hydrogen bonds | journal=Solid State Communications | publisher=Elsevier BV | volume=1 | issue=6 | year=1963 | issn=0038-1098 | doi=10.1016/0038-1098(63)90212-6 | pages=132–137}}

(quasielastic neutron scattering, QENS).

Finally, it is sometimes used for dynamic light scattering (also known by the more expressive term photon correlation spectroscopy).