Difference between revisions of "PbBi THickness CylinderBeam"
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| PbBi Thickness (mm) || #positrons/million electrons (GEANT4.9.6.p02|| #positrons/million electrons (G4Beamline) | | PbBi Thickness (mm) || #positrons/million electrons (GEANT4.9.6.p02|| #positrons/million electrons (G4Beamline) | ||
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− | | 1 || =<math>\pm</math> || | + | | 1 || 994,996,967,971,956=<math>\pm</math> || |
|- | |- | ||
| 1.5 || =<math>\pm</math> || | | 1.5 || =<math>\pm</math> || |
Revision as of 22:18, 8 February 2016
Initial rate study
2mm thick PbBi, 10 MeV, 1 cm cylindrical incident electron distribution
G4beamline pencil beam 10 cm radius
beam ellipse particle=e- nEvents=1000000 beamZ=0.0 beamX=0. beamY=0. \ sigmaX=10.0 sigmaY=10.0 sigmaXp=0.000 sigmaYp=0.000 \ meanMomentum=10. sigmaE=0. maxR=10.
Incident Electron spatial distribution and energy
Positron and Electron Momentum after the converter
PbBi Thickness (mm) | #positrons/million electrons (G4Beamline) | #positrons/million electrons (MCNPX) |
1 | 1169,1083,1068,1090,1088 =1100 | 401091 |
1.5 | 1723, 1668,1671, 1687,1726=1695 | 281728 |
2 | 1902,1921,1886,1967,1922=1920 | 301984 |
3 | 1920,1880,1883,1864,1857=1881 | 241986 |
4 | 1688, 1766, 1712, 1709, 1753=1726 | 331858 |
5 | 1569,1585,1509 ,1536,1551=1550 | 291646 |
7 | 1475,1450,1457,1428,1477 =1457 | 201541 |
10 | 1250,1180,1178,1186,1166=1192 | 331216 |
Dmitry's processing of Tony's GEANT simulations showing transverse phase space portrait (left) and longitudinal phase space portrait (right). Phase space portraits show coordinate x or y vs diveregense=px/pz or py/pz (or time vs kinetic energy ). Captions show:
1. geometric (not normalized) emittance for transverse and emittance for longitudinal phase space portraits (ellipse areas divided by "pi")
2. Twiss parameters
3. Ellipse centroid for longitudinal phase portrait
4. sqrt(beta*emittance) and sqrt(gamma*emittance) - half sizes of the projections of the ellipses on the coordinate and divergence axes respectively.
Electrons - RMS
Electrons - 68.2% core
Positrons - RMS
Positrons - 68.2% core
The plot below shows the energy deposited in MeV along the pipe. The Z axis is along the beam direction. The distance around the beam pipe is determine by taking the pipe radius (34.8 mm) and multiplying it by the Phi angle around the pipe. The bins are 1cm x 1cm.
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Below is energy deposited contributions from from photons(AVSzWg), positrons (AVSzWpos), and electrons.
Why is the positron hotspot upstream of the target? Because beam was going from right to left.
root commands used
TH2D *AVSz=new TH2D("AVSz","AVSz",100,-1000,0,12,-60,60) BeamPipeE->Draw("35.*atan(PosYmm/PosXmm):PosZmm>>AVSz","DepEmeV"); AVSz->Draw("colz");
Rate comparison with Energy and target thickness
- Difference with above simulation are that GEANT4 has SS windows and all created positrons that leave the target are counted , not just those going through a Sensitive detector downstream
6MeV
PbBi Thickness (mm) | #positrons/million electrons (GEANT4.9.6.p02 | #positrons/million electrons (G4Beamline) |
1 | 465,449,457,454,472 = | |
1.5 | = | |
2 | 396,418,394,415,395 = | |
3 | = | |
4 | 338,327,332,341,336= | |
5 | = | |
7 | = | |
10 | = |
8 MeV
PbBi Thickness (mm) | #positrons/million electrons (GEANT4.9.6.p02 | #positrons/million electrons (G4Beamline) |
1 | 994,996,967,971,956= | |
1.5 | = | |
2 | 1184,1212,1175,1194,1178= | |
3 | = | |
4 | 989,1013,975,962,956= | |
5 | = | |
7 | = | |
10 | = |
10 MeV
PbBi Thickness (mm) | #positrons/million electrons (GEANT4.9.6.p02 | #positrons/million electrons (G4Beamline) |
1 | = | |
1.5 | = | |
2 | 2445,2386,2321,2359,2368 = | |
3 | = | |
4 | 2087,2104,2121,2154,2118 = | |
5 | = | |
7 | = | |
10 | = |