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Dear all Gate users.</div>
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<div style=""><font color="#000000" face="Calibri, Helvetica, sans-serif"><span style="font-size: 12pt;">I have ran a simulation with 2 billions monoenergetic photon beam of E=0.1 keV traversing through a geometry of 3 thin air slabs contained in a box of dense
air(air with the same density as water). </span></font></div>
<div style=""><font color="#000000" face="Calibri, Helvetica, sans-serif"><span style="font-size: 12pt;">The geometry should
</span>fulfill<span style="font-size: 12pt;"> Fano´s theorem for a photon beam of E=0.1keV. As an actor i have used the dose actor and for the physics i have used
</span>Penelope<span style="font-size: 12pt;">. The dose of the big air box should get a "smoothly declining" </span></font><span style="color: rgb(0, 0, 0); font-family: Calibri, Helvetica, sans-serif;">behavior but at the boundaries</span><span style="color: rgb(0, 0, 0); font-family: Calibri, Helvetica, sans-serif; font-size: 12pt;"> of
respective slab i get a peak and a minimum in dose, see attached figure "doseprofile". Have anyone else had this problem? What can i do to fix it?</span></div>
<div style=""><span style="color: rgb(0, 0, 0); font-family: Calibri, Helvetica, sans-serif; font-size: 12pt;"><br>
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<div style=""><span style="color: rgb(0, 0, 0); font-family: Calibri, Helvetica, sans-serif; font-size: 12pt;">I have tried to change the "SetCutInRegion" fort the gammas, electrons and positrons to the lowest possible and it seems that it helps a bit but it
does not fix the problem. I have also tried to set the "stepHitType" of the detectors to "random" but the peaks are still there.</span><br>
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<div style=""><font color="#000000" face="Calibri, Helvetica, sans-serif"><span style="font-size: 12pt;">I have attached settings used for the geometry, beam, detector, materials and main simulation. I have also attached the resulting dose profile from the
big air box "doseprofile".</span></font></div>
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<div style=""><font color="#000000" face="Calibri, Helvetica, sans-serif"><span style="font-size: 12pt;">Any ideas on how i can fix this would
</span>really<span style="font-size: 12pt;"> be </span>appreciated.</font></div>
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<div style=""><font color="#000000" face="Calibri, Helvetica, sans-serif">Thanks for help!</font></div>
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<div style=""><span style="color: rgb(0, 0, 0); font-family: Calibri, Helvetica, sans-serif;">Regards,</span></div>
<div style=""><span style="color: rgb(0, 0, 0); font-family: Calibri, Helvetica, sans-serif;">Ludvig Syrén</span></div>
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