deletions | additions       diff --git a/Physical model.tex b/Physical model.tex  index 596e245..274ce5c 100644  --- a/Physical model.tex  +++ b/Physical model.tex 
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Let's describe these phenomena in a The  physical point characteristics  of view. these phenomena are now examined.  The optical intensity $I_0$ intensity, $I_0$,  of the laser beam is defined as $I_0=\frac{1}{S}\frac{d E}{dt}$, where $E$ is the beam energy and $S$ is  the beam surface. When emitted on the surface of  a medium surface, and  in the  absence of reflection, the laser beam is absorbed with an exponential decay along as a function of the  medium depth $z$: $I(z)=I_0 \exp(- \gamma z)$, where $\gamma$ is the absorption coefficient of the medium. We haveestimated  experimentally estimated  $\gamma$ by measuring the fraction of light which go through that is able to permeate  different thicknesses of the medium (0, 30, 50 50,  and 100 $\mu$m) with a laser beam energy measurement energy-measurement  device (QE50LP-S-MB-D0 energy detector, Gentec, Qu\'ebec, QC, Canada). We found respective transmitted powers of 100\%, 42\%, 28\% 28\%,  and 11\%: an exponential fit indicated that 11\%, with  $\gamma^{-1} \approx$ 40 $\mu m$ in our sample. sample as indicated by an exponential fit.