In X-ray photoelectron spectroscopy factor which characterizes the intensity distribution,
\(L(\gamma)\), of photoelectrons ejected by X-rays from isolated atoms at an angle
\(\gamma\) from the incident X-ray direction. In the dipole approximation,
\(L(\gamma) = 1 + ½\beta [3(\sin^{2}\gamma)/2-1]\).
Note: This formula relates to gases and is modified by the effects of elastic scattering when applied to solids. At the magic angle, \(L(\gamma) = 1\).
Source:
PAC, 2020, 92, 1781. 'Glossary of methods and terms used in surface chemical analysis (IUPAC Recommendations 2020)' on page 1820 (https://doi.org/10.1515/pac-2019-0404)