Hello Kaiyang Li, I'm still struggling with "forbid". I tried the simple geometry, too, but my simulation stops with "***Break*** segmentation violation" and I cannot proceed to even see the reconstructed image... this didn't happen before... Anyway, it seems the command is working somehow. When I tried to forbid the whole source by surrounding with the "forbidding" volume and start simulation, GATE gave me the message of "primaries were always generated in forbidden volumes!" and the simulation was shut down. Also, you can visualize the source by /gate/source/FictiveSource/visualize "count" "color" "size" This command should reflect the "forbid" as well, so we are supposed to be able to see the "forbidden" source... but... You can check how the "forbid" command works in GATE in GateSPSPosDistribution.cc line:150 After all, I cannot give you any solution to this problem. I'll still work on with this, so if you find anything new, please let me know. Taku <div class="gmail_quote">2012/12/10 Kaiyang Li <<a href="mailto:kl780@uowmail.edu.au" target="_blank">kl780@uowmail.edu.au</a>> <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"> <div> <div style="direction:ltr;font-size:10pt;font-family:Tahoma">Hi Taku, My name is Kaiyang Li, a GATE user. I have the problem of using "forbid" in my simulation. It seems that the forbid area is simply not forbidden at all. I have read all other questions, including yours. Have you figure it out yet? I have used GATE for half a year and run some other complex simulations successfully but for this forbid one, it seems something is wrong. Here is my simple code followed by the GATE instruction: /gate/world/daughters/name cold_area /gate/world/daughters/insert cylinder /gate/cold_area/vis/forceWireframe /gate/cold_area/vis/setColor green /gate/cold_area/geometry/setRmax 2.0 mm /gate/cold_area/geometry/setHeight 0.3 mm /gate/cold_area/setMaterial Water /gate/run/initialize /gate/source/addSource number1 /gate/source/number1/setActivity 37000000. becquerel /gate/source/number1/gps/particle gamma /gate/source/number1/setType backtoback /gate/source/number1/gps/monoenergy 511. keV /gate/source/number1/setForcedUnstableFlag true /gate/source/number1/setForcedHalfLife 6586 s /gate/source/number1/gps/type Volume /gate/source/number1/gps/shape Cylinder /gate/source/number1/gps/radius 4. mm /gate/source/number1/gps/halfz 0.15 mm /gate/source/number1/gps/centre 0. 0. 0. mm /gate/source/number1/gps/angtype iso /gate/source/number1/gps/Forbid cold_area /gate/source/number1/dump 1 /gate/source/list The reconstructed image shows that there is no forbidden area. Probably the forbidden command is not working, what do you think? Kind Regards, Kaiyang Li </div> </div> </blockquote></div> -- Hokkaido University, Graduate school of medicine, medical physics and engineering D1 北海道大学大学院医学研瘢雹究科医学物理工学分野 D1 Taku Yamanaka 山中琢 <a href="mailto:takuyama@med.hokudai.ac.jp" target="_blank">takuyama@med.hokudai.ac.jp</a> --