<html> <head> <meta http-equiv="Content-Type" content="text/html; charset=ks_c_5601-1987"> <style type="text/css" style="display:none;"></style> </head> <body dir="ltr"> <div id="divtagdefaultwrapper" style="font-size:12pt;color:#000000;background-color:#FFFFFF;font-family:Calibri,Arial,Helvetica,sans-serif;"> Dear gate users I would like to create 3-dimensional annulus shape of source. According to gate wiki (http://wiki.opengatecollaboration.org/index.php/Users_Guide_V7.0:Source), annulus shape is provided only for two dimensional plane source. Do you have any tips to make 3-dimensional annulus shape of source? or should I use geant4 instead? Regards, Wonmo Sung </div> </body> </html>