<div dir="ltr"><div><div><div><div>Hi Ane,<br><br></div>The extra volume inside trpd is basically a hole in your geometry.<br><br></div>My suggestion would be to use the volume "trap" which is accepted by GATE; the parameters are described here: <a href="http://geant4.web.cern.ch/geant4/UserDocumentation/UsersGuides/ForApplicationDeveloper/html/ch04.html">http://geant4.web.cern.ch/geant4/UserDocumentation/UsersGuides/ForApplicationDeveloper/html/ch04.html</a> (look for G4Trap).<br><br></div>Regards,<br></div>Débora<br><br><div><div><div><div><div><div><div><div class="gmail_signature" data-smartmail="gmail_signature"><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div><span style="border-collapse:separate;color:rgb(0,0,0);font-family:Helvetica;font-style:normal;font-variant:normal;font-weight:normal;letter-spacing:normal;line-height:normal;text-indent:0px;text-transform:none;white-space:normal;word-spacing:0px;border-spacing:0px"></span><span style="color:rgb(7,55,99)"><span style="font-family:tahoma,sans-serif"></span><span style="font-family:tahoma,sans-serif">Debora Salvado</span></span><br><div><span style="color:rgb(7,55,99)"><span style="font-family:tahoma,sans-serif">PhD Student<br></span></span></div><span style="color:rgb(7,55,99)"><span style="font-family:tahoma,sans-serif">University College London UCLH</span></span><span style="color:rgb(7,55,99)"><span style="font-family:tahoma,sans-serif"><br></span></span><span style="color:rgb(7,55,99)"><span style="font-family:tahoma,sans-serif">London </span></span><span style="color:rgb(7,55,99)"><span style="font-family:tahoma,sans-serif">UK</span></span><span style="color:rgb(12,52,61)"><span style="font-family:tahoma,sans-serif"></span></span><br></div></div></div></div></div></div></div></div>
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