deletions | additions       diff --git a/Physical model.tex b/Physical model.tex  index 274ce5c..a905fde 100644  --- a/Physical model.tex  +++ b/Physical model.tex 
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The We will now examine the involved  physicalcharacteristics of these  phenomena are now examined. involved in these experiments.  The optical 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 and in the absence of reflection, the laser beam is absorbed with an exponential decay 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 have experimentally estimated $\gamma$ by measuring the fraction of light that is able to permeate different thicknesses of the medium (0, 30, 50, and 100 $\mu$m) with a laser beam energy-measurement device (QE50LP-S-MB-D0 energy detector, Gentec, Qu\'ebec, QC, Canada). We found respective transmitted powers of 100\%, 42\%, 28\%, and 11\%, with $\gamma^{-1} \approx$ 40 $\mu m$ in our sample as indicated by an exponential fit.