[Gate-users] About Timing Window

Sebastien JAN sebastien.jan at cea.fr
Thu Nov 16 13:54:25 CET 2006


Hi Qingguo,

I will be out of my office during one week, I will be back to you ASAP 
about this problem

Cheers
Sebastien

qgxie at mail.hust.edu.cn wrote:
> Hi Gaters,
> 
> I aksed a question about timing window problem during the workshop held 
> at NSS/MIC.
> 
> I expected the time difference not lager than the timing window in the 
> coincidence events.
> 
> Attached please find cw100.mac and timediff.C(for root). In this case, 
> there are more than 50% coincidence events with the time difference 
> larger than the timing window(100ps).
> 
> Please help me to test it.
> 
> Thanks a lot.
> 
> Qingguo Xie
> 
> 
> ------------------------------------------------------------------------
> 
> # W O R L D
> /gate/world/geometry/setXLength 900 mm
> /gate/world/geometry/setYLength 900 mm
> /gate/world/geometry/setZLength 220 mm
> 
> # C Y L I N D R I C A L
> /gate/world/daughters/name cylindricalPET
> /gate/world/daughters/insert cylinder
> /gate/cylindricalPET/setMaterial Air
> /gate/cylindricalPET/geometry/setRmax 437.5 mm
> /gate/cylindricalPET/geometry/setRmin 412.5  mm
> /gate/cylindricalPET/geometry/setHeight 210 mm
> 
> # resector
> /gate/cylindricalPET/daughters/name rsector
> /gate/cylindricalPET/daughters/insert box
> /gate/rsector/placement/setTranslation 425 0 0 mm
> /gate/rsector/geometry/setXLength 25 mm
> /gate/rsector/geometry/setYLength 54 mm
> /gate/rsector/geometry/setZLength 162 mm
> /gate/rsector/setMaterial Air
> 
> # module
> /gate/rsector/daughters/name module
> /gate/rsector/daughters/insert box
> /gate/module/geometry/setXLength 25 mm
> /gate/module/geometry/setYLength 54 mm
> /gate/module/geometry/setZLength 54 mm
> /gate/module/setMaterial Air
> 
> #crystal
> /gate/module/daughters/name crystal
> /gate/module/daughters/insert box
> /gate/crystal/geometry/setXLength 25 mm
> /gate/crystal/geometry/setYLength 6.45 mm
> /gate/crystal/geometry/setZLength 6.45 mm
> /gate/crystal/setMaterial Air
> 
> # layer 0
> /gate/crystal/daughters/name LSO
> /gate/crystal/daughters/insert box
> /gate/LSO/geometry/setXLength 25 mm
> /gate/LSO/geometry/setYLength 6.45 mm
> /gate/LSO/geometry/setZLength 6.45 mm
> /gate/LSO/setMaterial LSO
> 
> # R E P E A T C R Y S T A L
> /gate/crystal/repeaters/insert cubicArray
> /gate/crystal/cubicArray/setRepeatNumberX 1
> /gate/crystal/cubicArray/setRepeatNumberY 8
> /gate/crystal/cubicArray/setRepeatNumberZ 8
> /gate/crystal/cubicArray/setRepeatVector 0 6.75 6.75 mm
> #repeat module
> /gate/module/repeaters/insert linear
> /gate/module/linear/setRepeatNumber 3
> /gate/module/linear/setRepeatVector 0 0 54 mm
> # repeat rsector
> /gate/rsector/repeaters/insert ring
> /gate/rsector/ring/setRepeatNumber 48 
> 
> # A T T A C H S Y S T E M
> /gate/systems/cylindricalPET/rsector/attach rsector
> /gate/systems/cylindricalPET/module/attach module
> /gate/systems/cylindricalPET/crystal/attach crystal
> /gate/systems/cylindricalPET/layer0/attach LSO
> 
> # A T T A C H L A Y E R SD
> /gate/LSO/attachCrystalSD
> 
> # P H A N T O M
> /gate/world/daughters/name phantom
> /gate/world/daughters/insert cylinder 
> /gate/phantom/geometry/setRmax 100 mm
> /gate/phantom/geometry/setHeight 190 mm
> /gate/phantom/placement/setTranslation 0 0 0 mm
> /gate/phantom/setMaterial Water 
> # A T T A C H P H A N T O M S D
> /gate/phantom/attachPhantomSD
> 
> 
> # P H Y S I C S
> /gate/physics/gamma/selectCompton standard
> /gate/physics/gamma/selectPhotoelectric standard
> /gate/physics/gamma/selectRayleigh lowenergy
> /gate/physics/setElectronCut 1000. km
> /gate/physics/setXRayCut 1. GeV
> /gate/physics/setDeltaRayCut 1. GeV
> /gate/physics/verbose 2
> 
> 
> # I N I T I A L I Z E
> /gate/systems/cylindricalPET/verbose 0
> /gate/geometry/enableAutoUpdate
> /run/initialize
> 
> # S O U R C E S
> /gate/source/addSource twogamma
> /gate/source/twogamma/setActivity 1000000 becquerel
> /gate/source/twogamma/setType backtoback
> /gate/source/twogamma/gps/particle gamma
> /gate/source/twogamma/gps/energytype Mono
> /gate/source/twogamma/gps/monoenergy 0.511 MeV
> /gate/source/twogamma/gps/type Volume
> /gate/source/twogamma/gps/shape Cylinder
> /gate/source/twogamma/gps/radius 100 mm
> /gate/source/twogamma/gps/halfz 95 mm
> /gate/source/twogamma/gps/angtype iso
> /gate/source/twogamma/gps/mintheta 0. deg
> /gate/source/twogamma/gps/maxtheta 180. deg
> /gate/source/twogamma/gps/minphi 0. deg
> /gate/source/twogamma/gps/maxphi 360. deg
> /gate/source/twogamma/gps/centre 0. 0. 0. cm
> /gate/source/list
> 
> 
> # D I G I T I Z E R
> /gate/digitizer/Singles/insert adder
> /gate/digitizer/Singles/insert readout
> /gate/digitizer/Singles/readout/setDepth 2
> /gate/digitizer/Coincidences/setWindow 0.1 ns
> /gate/digitizer/Coincidences/minSectorDifference 10
> 
> /gate/systems/cylindricalPET/describe
> 
> # V E R B O S I T Y
> /control/verbose 0
> /grdm/verbose 0
> /run/verbose 0
> /event/verbose 0
> /tracking/verbose 0
> /gate/application/verbose 0
> /gate/generator/verbose 0
> /gate/stacking/verbose 0
> /gate/event/verbose 0
> /gate/source/verbose 0
> 
> # O U T P U T
> # ASCII
> /gate/output/ascii/setOutFileSizeLimit 100000000
> /gate/output/ascii/setOutFileHitsFlag 0
> /gate/output/ascii/setOutFileSinglesFlag 0
> /gate/output/ascii/setOutFileCoincidencesFlag 1
> 
> # ROOT
> /gate/output/root/setFileName cwbug
> /gate/output/root/setRootNtupleFlag 0
> /gate/output/root/setRootHitFlag 0
> /gate/output/root/setRootSinglesFlag 0
> /gate/output/root/setRootCoincidencesFlag 1
> /gate/output/root/setSaveRndmFlag 1
> 
> # S T A R T
> /gate/application/setTimeSlice 1 s
> /gate/application/setTimeStart 0 s
> /gate/application/setTimeStop  1 s
> /gate/application/startDAQ
> 
> exit
> 
> 
> ------------------------------------------------------------------------
> 
> void timediff( char src[200] )
> {
>   FILE *outf;
>   outf=fopen("timeinf.txt","w");
>   TFile *pRootFile = new TFile(src);
>   TTree *pTreeCoin = (TTree*)pRootFile->Get("Coincidences");
>   double time1;
>   double time2;
>   int eventID1;
>   int nentries = (int) pTreeCoin -> GetEntries();
>   int nBug=0;  
> 
>   pTreeCoin->SetBranchAddress("time1",&time1);
>   pTreeCoin->SetBranchAddress("time2",&time2);
>   pTreeCoin->SetBranchAddress("eventID1",&eventID1);
> 
>   for(int i=0 ; i<nentries ; i++){
>     pTreeCoin->GetEntry(i);
>     fprintf(outf,"%1.12lf, %1.12lf\n",time1,time2);
>     if( fabs(time1-time2)*1.0e12 > 100. ) nBug++;
>   }
>   printf("Total Coincidences event %d, coincidences events out of window %d\n", nentries, nBug);
>   delete pTreeCoin;
>   fclose(outf);
> }
> 
> 
> ------------------------------------------------------------------------
> 
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