<FONT face="Default Sans Serif,Verdana,Arial,Helvetica,sans-serif" size=2><DIV><DIV><FONT color=#990099><FONT color=#000000>We are performing such simulations with two different type of detecors. The trick we are using is to run each simulation twice. The first time, detector type #1 is attached as crystalSD, and the phantom and detector type #2 are attached as phantomSD. The second time, detector type #2 is attached as crystalSD, and the phantom and detector type #1 are attached as phantomSD. By using the same random seed for both runs, and not calling any energy or time blurring (which use the random seed), we get two correlated runs that we then sort with our own software. Our system is set up as cylindricalPET, and our output are singles (gateSingles.dat).</FONT></FONT></DIV><DIV> </DIV><DIV>I hope this helps.</DIV><DIV> </DIV><DIV>Martin</DIV><DIV> </DIV><DIV><DIV><BR><DIV><DIV>************************************************<BR>Martin Janecek, Ph.D.<BR>Washington U. School of Medicine<BR>Dept. of Radiological Sciences<BR>Campus Box 8225<BR>510 South Kingshighway<BR>St. Louis, MO 63110<BR></DIV></DIV></DIV></DIV><blockquote style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px"><FONT face="Default Monospace,Courier New,Courier,monospace" size=2 >Dear all,<BR><BR>Just a basic question concerning the possibility to simulate two types <BR>of detector in one simulation.<BR>Is it possible to attach two different geometries (say a cylindricalPET <BR>+ a box for instance) with each a different detection medium ?<BR><BR>We would like to add to an already simulated µPET device a new detection <BR>medium whose geometry is defined as a box and coupled to one side of the <BR>µPET.<BR>My question is basically, is it possible to perform such a simulation <BR>without too much effort (i.e. by adding a specific class or deriving an <BR>existing class) ?<BR><BR>Thank you so much for your help<BR><BR><BR>Thomas Carlier<BR>University Hospital<BR>Nuclear Medicine Dept<BR>Nantes, France</FONT><br></blockquote></DIV></FONT>