Abstract

Resonance radiation may be absorbed and reemitted many times in an atomic vapor before it reaches the boundary of a vessel. This effect is known as “radiation trapping”. It has to be taken into account in many spectroscopic measurements. The mathematical description for trapping in an infinite slab of width L (which is equivalent to a cylindrical vessel of height L with reflecting side walls) is given by the equation of radiative transfer and the rate equation for the excited-state atoms n(x,t) where µ is the cosine of the angle with the x-axis, which is normal to the boundary of the slab. Otherwise we used the common notation of Ref. ¹.

© 1992 IQEC