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<p class="MsoNormal"><span style="font-size:11.0pt">This just sounds like the dependence of intensity on incident angle which should be proportional to cos^2(theta) (or sin^2(theta) depending on how you’re defining theta). So I can see a situation where the
laser goes through the foils when it is exactly perpendicular to the foils if the laser power is very high. Then as you aim the laser to smaller angles (wrt the horizontal), the intensity goes down allowing the foils to absorb more. At some point (I guess
30-40 degrees as you observed), more of the laser is reflected than absorbed.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;color:black">--</span><span style="color:black"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Arial",sans-serif;color:#181A1B">Eddie Hansen</span><span style="color:black"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Arial",sans-serif;color:#181A1B">Research Scientist</span><span style="color:black"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Arial",sans-serif;color:#181A1B">Flash Center for Computational Science</span><span style="color:black"><o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
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<p class="MsoNormal" style="margin-bottom:12.0pt"><b><span style="font-size:12.0pt;color:black">From:
</span></b><span style="font-size:12.0pt;color:black">flash-users <flash-users-bounces@flash.rochester.edu> on behalf of Kaldawi, Thomas <Tkal@lle.rochester.edu><br>
<b>Date: </b>Wednesday, July 12, 2023 at 2:55 PM<br>
<b>To: </b>flash-users@flash.rochester.edu <flash-users@flash.rochester.edu><br>
<b>Subject: </b>[FLASH-USERS] Laser Energy Depositing<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt;color:black">Hello, <o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt;color:black"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt;color:black">I have two foils in the Laser Slab simulation (one at 30nm and the other at 0.5 microns), and the laser tends to go through the foils instead of reflecting/ablating them. I noticed that if I aim
the laser at a small enough angle from the horizontal axis, the lasers will reflect off the foils as expected; however, at this current angle they just get absorbed into the foil which should not be happening. I do not know at what angle the lasers convert
from relfecting to absorbing, but I would say it is around 30-40 degrees from the horizontal.<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt;color:black"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt;color:black">Does anyone have a solution to this? Maybe there is a setting in the laser energy that changes this?<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt;color:black"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt;color:black">Thank you, <o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt;color:black"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt;color:black">Thomas Kaldawi<o:p></o:p></span></p>
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