Difference between revisions of "G4Beamline PbBi"
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Development of a Positron source using a PbBi converter and a Solenoid | Development of a Positron source using a PbBi converter and a Solenoid | ||
− | = | + | =Conclusions= |
− | + | #A 0.3 (0.6) Tesla Solenoid with a diameter to allow a 9.74 (3.94) cm diameter pipe would collect a positron per thousand incident electrons on a 2mm thick LBE target with 0.25 mm thick SS windows. | |
+ | # A 15 cm long, 0.2 Tesla solenoid with a 3.94 diameter beam pipe would collect a positron per two thousand electrons impinging a 2mm thick LBE target with 0.25 mm thick SS windows. | ||
+ | #A 4 Tesla Solenoid will remove beam pipe heating from scattered electrons downstream of the target when using a 3.94 cm diameter beam pipe. | ||
− | + | =Reports= | |
− | + | [[Niowave_Report_11-30-2015]] | |
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+ | deadline 4/12/16 | ||
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+ | ==[[Niowave_9-2015]]== | ||
+ | ==[[Niowave_10-2015]]== | ||
+ | ==[[Niowave_11-2015]]== | ||
+ | ==[[Niowave_12-2015]]== | ||
+ | ==[[Niowave_1-2016]]== | ||
+ | ==[[Niowave_2-2016]]== | ||
+ | ==[[Niowave_3-2016]]== | ||
+ | ==[[Niowave_4-2016]]== | ||
+ | ==[[Niowave_5-2016]]== | ||
+ | ==[[Niowave_6-2016]]== | ||
+ | =Task List= | ||
− | + | 0.) 34.8 mm pipe, 0.0 -> 0.5 Tesla, E= 6,8,10 MeV. | |
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+ | 1.) Create a positron (10,000 positrons) and electron event file containing t,x,y,z,Px,Py,Pz for positrons exiting the solenoid and an incident Gaussian beam 1cm in diameter and with a sigma of 1cm. | ||
− | + | compare distributions with and without solenoid. | |
− | + | 2.) Determine the back ground when using a 3.48 diameter beam pipe and Solenoid field of 0.2 for a NaI detector placed at | |
− | + | 3.) Experiment, install dipole and solenoid in the tunnel. | |
− | + | =Beam Pipe Heating= | |
+ | [[PbBi_BeamPipeHeatin_2015]] | ||
− | + | =Converter target properties= | |
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− | + | [[PbBi_NioWave_TargetProperties_2015]] | |
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− | + | =Target thickness optimization= | |
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− | + | ==[[PbBi_THickness_CylinderBeam]]== | |
− | + | ==[[PbBi_THickness_GaussBeam]]== | |
+ | == [[PbBi_THickness_PntSource]]== | ||
+ | =Solenoid= | ||
+ | ==Uniform ideal Solenoid== | ||
− | + | === [[PbBi_BeamPipeHeating_w_Solenoid_2015]]=== | |
+ | ===[[PbBi_60cmLong_Solenoid_Collection_Efficiency_2015]]=== | ||
− | + | ==Positron & Electron event files== | |
− | + | [[PbBi_PosEventFiles_VaccumGaps_2015]] | |
+ | [[PbBi_PosEventFiles_NoGaps_2016]] | ||
+ | ==Solenoid Map== | ||
+ | Inner Radiusu= | ||
+ | Outer Radius = | ||
− | + | Length = | |
− | + | Current= | |
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+ | Magnetic Field Map in cylindrical coordinates (Z & R) from Niowave | ||
+ | =Rear Window Thickness= | ||
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− | + | Question: Will a thicker downstream exit window increase the positron production efficiency by providing more material for a brehm photon to pair produce in? | |
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− | + | Positrons were counted exiting a ideal 0.2 Tesla solenoid that was 15 cm long. A ten MeV electron beam with a 0.5 cm cylindrical radius impinged a 2mm thick PbBi liquid target that had a surface area of 2.54 cm x 2.54 cm. A 0.25 mm thick stainless steel entrance window was used. | |
+ | Target is at -106 mm, entrance SS window is at -108.25 mm , exit SS window is at -103.75 mm, A sensitive detector for positron is placed at Z= +44mm. The sensitive detector is a cylinder of radius 11.74 cm. | ||
{| border="1" | {| border="1" | ||
{| border="1" | {| border="1" | ||
− | | | + | | SS Exit WIndow Thickness (mm) || Positrons/Million electrons |
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− | | | + | |0.0 || 1142,1096,1149,1073,1083 = 1109 +/- 35 |
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− | + | | 0.25 || 774,836,800,785,798 = 798 +/- 23 | |
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− | | | + | | 0.5 || 693,704,713,697,715 = 704 +/- 10 |
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− | | | + | | 1.0 || 587,606,548,592,550 =577 +/- 26 |
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− | + | ;Conclusion 1: Positron production efficiency improves when the exit window is made thinner | |
− | + | ;Conclusion 2 : You loose about 28 +/- 4 % of the positrons in the 0.25 mm thick SS exit window. | |
− | + | =Background studies= | |
− | + | ==Brem Spectrum== | |
− | + | Below is the photon energy distribution (from Brem & pair production) using a 2mm Pb target for two different incident electron energies; 6 and 10 MeV. The photons are 1 cm downstream of the target and intersection a large forward region. | |
− | + | [[File:PbBi_Brem_6-10MeV_4-7-16.png | 200 px]] | |
+ | insert photon spacial distributions | ||
− | + | Now move the scoring region downstream to a position representing the location of a NaI detector. | |
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=Beam Line Design= | =Beam Line Design= |
Latest revision as of 21:39, 8 June 2016
Development of a Positron source using a PbBi converter and a Solenoid
Conclusions
- A 0.3 (0.6) Tesla Solenoid with a diameter to allow a 9.74 (3.94) cm diameter pipe would collect a positron per thousand incident electrons on a 2mm thick LBE target with 0.25 mm thick SS windows.
- A 15 cm long, 0.2 Tesla solenoid with a 3.94 diameter beam pipe would collect a positron per two thousand electrons impinging a 2mm thick LBE target with 0.25 mm thick SS windows.
- A 4 Tesla Solenoid will remove beam pipe heating from scattered electrons downstream of the target when using a 3.94 cm diameter beam pipe.
Reports
deadline 4/12/16
Niowave_9-2015
Niowave_10-2015
Niowave_11-2015
Niowave_12-2015
Niowave_1-2016
Niowave_2-2016
Niowave_3-2016
Niowave_4-2016
Niowave_5-2016
Niowave_6-2016
Task List
0.) 34.8 mm pipe, 0.0 -> 0.5 Tesla, E= 6,8,10 MeV.
1.) Create a positron (10,000 positrons) and electron event file containing t,x,y,z,Px,Py,Pz for positrons exiting the solenoid and an incident Gaussian beam 1cm in diameter and with a sigma of 1cm.
compare distributions with and without solenoid.
2.) Determine the back ground when using a 3.48 diameter beam pipe and Solenoid field of 0.2 for a NaI detector placed at
3.) Experiment, install dipole and solenoid in the tunnel.
Beam Pipe Heating
Converter target properties
PbBi_NioWave_TargetProperties_2015
Target thickness optimization
PbBi_THickness_CylinderBeam
PbBi_THickness_GaussBeam
PbBi_THickness_PntSource
Solenoid
Uniform ideal Solenoid
PbBi_BeamPipeHeating_w_Solenoid_2015
PbBi_60cmLong_Solenoid_Collection_Efficiency_2015
Positron & Electron event files
PbBi_PosEventFiles_VaccumGaps_2015
PbBi_PosEventFiles_NoGaps_2016
Solenoid Map
Inner Radiusu=
Outer Radius =
Length =
Current=
Magnetic Field Map in cylindrical coordinates (Z & R) from Niowave
Rear Window Thickness
Question: Will a thicker downstream exit window increase the positron production efficiency by providing more material for a brehm photon to pair produce in?
Positrons were counted exiting a ideal 0.2 Tesla solenoid that was 15 cm long. A ten MeV electron beam with a 0.5 cm cylindrical radius impinged a 2mm thick PbBi liquid target that had a surface area of 2.54 cm x 2.54 cm. A 0.25 mm thick stainless steel entrance window was used.
Target is at -106 mm, entrance SS window is at -108.25 mm , exit SS window is at -103.75 mm, A sensitive detector for positron is placed at Z= +44mm. The sensitive detector is a cylinder of radius 11.74 cm.
SS Exit WIndow Thickness (mm) | Positrons/Million electrons |
0.0 | 1142,1096,1149,1073,1083 = 1109 +/- 35 |
0.25 | 774,836,800,785,798 = 798 +/- 23 |
0.5 | 693,704,713,697,715 = 704 +/- 10 |
1.0 | 587,606,548,592,550 =577 +/- 26 |
- Conclusion 1
- Positron production efficiency improves when the exit window is made thinner
- Conclusion 2
- You loose about 28 +/- 4 % of the positrons in the 0.25 mm thick SS exit window.
Background studies
Brem Spectrum
Below is the photon energy distribution (from Brem & pair production) using a 2mm Pb target for two different incident electron energies; 6 and 10 MeV. The photons are 1 cm downstream of the target and intersection a large forward region.
insert photon spacial distributions
Now move the scoring region downstream to a position representing the location of a NaI detector.