<HTML dir=ltr><HEAD><TITLE>[Gate-users] isotropic emission from a rod source ?</TITLE> <META http-equiv=Content-Type content="text/html; charset=unicode"> <META content="MSHTML 6.00.6000.16544" name=GENERATOR></HEAD> <BODY> <DIV id=idOWAReplyText1767 dir=ltr> <DIV dir=ltr><FONT face=Arial color=#000000 size=2>And please tell us the Xposition for your two sources two. </FONT></DIV> <DIV dir=ltr><FONT face=Arial size=2></FONT> </DIV> <DIV dir=ltr><FONT face=Arial size=2>If you have sources very close to PET and plot detection position only for coincidences, you would see</FONT></DIV> <DIV dir=ltr><FONT face=Arial size=2>the limited Y, Z range due to geometrical acceptance.</FONT> </DIV> <DIV dir=ltr><FONT face=Arial color=#000000 size=2></FONT> </DIV></DIV> <DIV id=idSignature4379 dir=ltr><PRE>Yu Chen, Ph.D. University of Massachusetts Medical School Division of Nuclear Medicine 55 Lake Avenue North Worcester, MA 01655-0243 Phone: (508) 856-6123 Fax: (508) 856-4572</PRE></DIV> <DIV dir=ltr><BR> <HR tabIndex=-1> <FONT face=Tahoma size=2><B>From:</B> gate-users-bounces@lists.healthgrid.org on behalf of Chen, Yu<BR><B>Sent:</B> Mon 12/10/2007 11:01 PM<BR><B>To:</B> Joon Young Suk; gate-users@lists.healthgrid.org<BR><B>Subject:</B> RE: [Gate-users] isotropic emission from a rod source ?<BR></FONT><BR></DIV> <DIV dir=ltr> <DIV id=idOWAReplyText65048 dir=ltr> <DIV dir=ltr><FONT face=Arial color=#000000 size=2>How did you get those two plots?</FONT></DIV> <DIV dir=ltr><FONT face=Arial size=2>Using Singles or Coincidences?</FONT></DIV> <DIV dir=ltr><FONT face=Arial size=2></FONT> </DIV> <DIV dir=ltr><FONT face=Arial size=2>It seems that photons you recorded are even not isotropical (peak in y=0) in transverse plane.</FONT></DIV> <DIV dir=ltr><FONT face=Arial size=2>I do not understand what are those scattered points around central points in your left plot.</FONT></DIV> <DIV dir=ltr><FONT face=Arial size=2></FONT> </DIV> <DIV dir=ltr><FONT face=Arial size=2>You better put your PET geometry and coincidence module macro too.</FONT></DIV> <DIV dir=ltr><FONT face=Arial size=2></FONT> </DIV> <DIV dir=ltr><FONT face=Arial size=2>And please plot your sourcePosX,Y,Z in Singles.</FONT></DIV> <DIV dir=ltr><FONT face=Arial size=2>   </FONT></DIV> <DIV dir=ltr><FONT face=Arial color=#000000 size=2></FONT> </DIV></DIV> <DIV id=idSignature96355 dir=ltr><PRE>Yu Chen, Ph.D. University of Massachusetts Medical School Division of Nuclear Medicine 55 Lake Avenue North Worcester, MA 01655-0243 Phone: (508) 856-6123 Fax: (508) 856-4572</PRE></DIV> <DIV dir=ltr><BR> <HR tabIndex=-1> <FONT face=Tahoma size=2><B>From:</B> gate-users-bounces@lists.healthgrid.org on behalf of Joon Young Suk<BR><B>Sent:</B> Mon 12/10/2007 6:55 PM<BR><B>To:</B> gate-users@lists.healthgrid.org<BR><B>Subject:</B> [Gate-users] isotropic emission from a rod source ?<BR></FONT><BR></DIV> <DIV> <P><FONT size=2>I built two rod sources which set as isotropic sources, but <BR>simulation result show most data have been acquired from the <BR>horizontal plane.<BR>Please check my result in the following link :<BR><BR><A href="http://www.joonyoung.net/root_result_2007-12-10.jpg">http://www.joonyoung.net/root_result_2007-12-10.jpg</A><BR><BR>Could you please find out what is my problem.<BR>Here is a part of my macro ;<BR><BR><BR>##### PHANTOM GEOMETRY ##############<BR>## Cylindrical phantom has two rod sources ####<BR><BR># H E A D<BR>/gate/world/daughters/name phantomHead<BR>/gate/world/daughters/insert cylinder<BR>/gate/phantomHead/placement/setTranslation {phXposition} 0. 0. mm<BR>/gate/phantomHead/setMaterial Air<BR>/gate/phantomHead/geometry/setRmax 22.5 mm<BR>/gate/phantomHead/geometry/setHeight 50. mm<BR>/gate/phantomHead/vis/forceWireframe<BR>/gate/phantomHead/vis/setColor blue<BR>/gate/geometry/update<BR><BR># Add Rods for source confinement<BR><BR># ROD0 : rod at right-side (positive x-axis)<BR># Diameter : 1.0 mm<BR>/gate/phantomHead/daughters/name rod0<BR>/gate/phantomHead/daughters/insert cylinder<BR>/gate/rod0/geometry/setRmax 0.5 mm<BR>/gate/rod0/geometry/setRmin 0.0 mm<BR>/gate/rod0/geometry/setHeight 50. mm<BR>/gate/rod0/placement/setTranslation {rod0Xposition} 0. 0. mm<BR>/gate/rod0/setMaterial Water<BR>/gate/rod0/vis/setColor red<BR><BR># ROD1 : rod at left-side(negative x-axis)<BR>/gate/phantomHead/daughters/name rod1<BR>/gate/phantomHead/daughters/insert cylinder<BR>/gate/rod1/geometry/setRmax 0.5 mm<BR>/gate/rod1/geometry/setRmin 0.0 mm<BR>/gate/rod1/geometry/setHeight 50. mm<BR>/gate/rod1/placement/setTranslation {rod1Xposition} 0. 0. mm<BR>/gate/rod1/setMaterial Water<BR>/gate/rod1/vis/setColor red<BR><BR># PHANTOM defined as SENSITIVE<BR>/gate/phantomHead/attachPhantomSD<BR><BR><BR>###################################################################<BR># S O U R C E S<BR>#### two rod sources<BR>## rodsource0 -> confines to rod0 in the phantom<BR>## rodsource1 -> confiines  to rod1 in the phantom<BR>###################################################################<BR>/gate/source/addSource rodsource0<BR>/gate/source/rodsource0/setActivity {activity} becquerel<BR>/gate/source/rodsource0/setType backtoback<BR>/gate/source/rodsource0/gps/particle gamma<BR>/gate/source/rodsource0/gps/energytype Mono<BR>/gate/source/rodsource0/gps/monoenergy 0.511 MeV<BR>/gate/source/rodsource0/gps/type Volume<BR>/gate/source/rodsource0/gps/shape Cylinder<BR>/gate/source/rodsource0/gps/centre {r0sourceXposition} 0. 0. mm<BR>/gate/source/rodsource0/gps/radius 0.5 mm<BR>/gate/source/rodsource0/gps/halfz 25. mm<BR>/gate/source/rodsource0/gps/angtype iso<BR>/gate/source/rodsource0/gps/confine rod0_P<BR><BR>/gate/source/addSource rodsource1<BR>/gate/source/rodsource1/setActivity {activity} becquerel<BR>/gate/source/rodsource1/setType backtoback<BR>/gate/source/rodsource1/gps/particle gamma<BR>/gate/source/rodsource1/gps/energytype Mono<BR>/gate/source/rodsource1/gps/monoenergy 0.511 MeV<BR>/gate/source/rodsource1/gps/type Volume<BR>/gate/source/rodsource1/gps/shape Cylinder<BR>/gate/source/rodsource1/gps/centre {r1sourceXposition} 0. 0. mm<BR>/gate/source/rodsource1/gps/radius 0.5 mm<BR>/gate/source/rodsource1/gps/halfz 25. mm<BR>/gate/source/todsource1/gps/angtype iso<BR>/gate/source/rodsource1/gps/confine rod1_P<BR><BR>### ROOT ####<BR>/gate/output/root/setSaveRndmFlag 0<BR>/gate/output/root/setFileName {outFile}<BR>/gate/output/root/setRootHitFlag 0<BR>/gate/output/root/setRootSinglesFlag 1<BR>/gate/output/root/setRootCoincidencesFlag 1<BR>/gate/output/root/setRootNtupleFlag 0<BR><BR># D A T A  A C Q U I S I T I O N<BR>/gate/application/setTimeSlice {timeSlice} s<BR>/gate/application/setTimeStart 0. s<BR>/gate/application/setTimeStop {timeStop} s<BR><BR>###### START DAQ #######<BR>/gate/application/startDAQ<BR><BR><BR><BR><BR>Thank you<BR><BR>_______________________________________________<BR>Gate-users mailing list<BR>Gate-users@lists.healthgrid.org<BR><A href="http://lists.healthgrid.org/mailman/listinfo/gate-users">http://lists.healthgrid.org/mailman/listinfo/gate-users</A><BR><BR></FONT></P></DIV></DIV></BODY></HTML>