|Message: propagation speed of optical photons||Not Logged In (login)|
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I was looking at the propagation speed of optical photons in a lead fluoride crystal (see attached gdml file) I see slower propagation of light than I would expect from the refraction index that I put in.
Photon energy 2 eV, time for 100 mm = 0.619201 nsec corresponds to n=1.856 when the input is 1.762 Photon energy 4 eV, time for 100 mm = 0.789297 nsec corresponds to n=2.399 when the input is 1.92658
Attachment: http://hypernews.slac.stanford.edu/HyperNews/geant4/get/AUX/2015/04/03/09.41-9681-opticalphothon-4eV.mac http://hypernews.slac.stanford.edu/HyperNews/geant4/get/AUX/2015/04/03/09.41-71382-opticalphothon.mac http://hypernews.slac.stanford.edu/HyperNews/geant4/get/AUX/2015/04/03/09.41-21420-ecrystal_color__PbF2.gdml
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