The absorption coefficient α {\displaystyle \alpha } now becomes the TPA coefficient β {\displaystyle \beta } . Le coefficient d'absorption α devient le coefficient ADP β.
2.
The absorption of atomic line radiation may be described by an absorption coefficient κ {\displaystyle \kappa } with units of 1/length. L'absorption d'une ligne de rayonnement atomique peut être décrite par un coefficient d'absorption κ
3.
The absorption coefficient is given by: κ ′ = h ν 4 π ( n 1 B 12 − n 2 B 21 ) {\displaystyle \kappa '={\frac {h\nu }{4\pi }}~(n_{1}B_{12}-n_{2}B_{21})\,} where B 12 {\displaystyle B_{12}} and B 21 {\displaystyle B_{21}} are the Einstein coefficients for photo absorption and induced emission respectively. Le coefficient d'absorption est donné par : κ ′ = h ν 4 π ( n 1 B 12 − n 2 B 21 )
