Difference between revisions of "DV RunGroupC Moller"

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Simulating the Moller scattering background for EG12
 
Simulating the Moller scattering background for EG12
 +
=Docker=
 +
==[[Set up Docker Container]]==
 +
=[[DV_XSECT|Moller Differential Cross-Section]]=
  
 
=GEANT4 Simulation of Moller Events=
 
=GEANT4 Simulation of Moller Events=
  
−
Determine the Moller background using an LH2 target to check the physics in GEANT4
+
==  [[LH2 target|Simulation Setup]]==
 +
Use GEANT4 via GEMC to estimate the Moller background for electron scattering experiments in JLab's Hall B.  The first step towards this goal is to use GEANT4 without the GEMC infrastructure to create event (LUND) files that will be used as input events for GEMC.
  
−
Incident electron energy varies from 1-11 GeV.
+
==[[DV_Moller_LH2 | Benchmark GEANT4's Moller scattering prediction with the theoretical cross section using LH2]]==
  
−
LH2 target is a cylinder with a 1.5 cm diameter and 1 cm thickness.
 
−
  (''Following dimensions listed on page 8 of'' [[File:PHY02-33.pdf‎]])
 
  
−
'''Numbers Moller electrons per incident electron.'''
 
−
  ''While 2nd and 3rd generations are created, only 2 2nd generation daughter particles are created for 1E6 incident particles.  All knock on electrons are not counted.''
 
  
−
=='''[[Momentum distributions in the Lab Frame.]]''' ==
+
===Comparison of simulation vs. the theoretical Møller differential cross section using 11 GeV electrons impinging LH2===
  
−
[[File:FnlMom.png]][[File:MolMom.png]]
+
[[Converting to barns|Converting the number of scattered electrons per scattering angle theta to a differential cross-section in barns.]]
  
−
=='''[[Momentum distributions in the Center of Mass Frame.]]'''==
+
[[File:XSect_new_zoom.png|frame|center|alt=Experimental and Theoretical Moller Differential Cross-Section in Center of Mass Frame Frame|'''Figure 5c:''' The experimental and theoretical Moller electron differential cross-section for an incident 11 GeV(Lab) electron in the Center of Mass frame of reference.]]
−
===Estimated Momentum Distribution===
 
  
 +
=Change to a NH3 Target=
 +
[[Replacing the LH2 target with an NH3 target]]
  
−
[[DV_Calculations_of_4-momentum_components]]
+
==[[DV_Moller_NH3|Benchmark GEANT4's Moller scattering prediction with the theoretical cross section using NH3]]==
  
−
For an incoming electron with momentum of 11GeV, we should find the momentum in the center of mass to be around '''53 MeV''' which is confirmed in the the data/plots.
+
==Comparison of simulation vs. the theoretical Møller differential cross section using 11 GeV electrons impinging NH3==
  
 +
[[Converting to barns|Converting the number of scattered electrons per scattering angle theta to a differential cross-section in barns.]]
  
−
{| border="1"
+
[[File:XSect_NH3.png|frame|center|alt=Theoretical and Simulated Moller Differential Cross-Section in Center of Mass Frame Frame|'''Figure 5c:''' The theoretical and simulated Moller electron differential cross-section for an incident 11 GeV(Lab) electron in the Center of Mass frame of reference for NH3 target.]]
−
|-
+
 
−
! KE<sub>i</sub>
+
==LH2 Vs. NH3==
−
! Px<sub>i</sub>
+
===[[DV_Moller_NH3_LH2|Benchmark GEANT4's Moller scattering prediction for NH3 and LH2]]===
−
! Py<sub>i</sub>
+
 
−
! Pz<sub>i</sub>
+
 
−
! x<sub>i</sub>
+
==Effects Due to Target Material==
−
! y<sub>i</sub>
+
===[[DV_Target_Density|Target Density]]===
−
! z<sub>1</sub>
+
 
−
! KE<sub>f</sub>
+
 
−
! Px<sub>f</sub>
+
===[[DV_a_z_target|Atomic Mass and Electron Number Effects]]===
−
! Py<sub>f</sub>
+
 
−
! Pz<sub>f</sub>
+
==[[Calculating the differential cross-sections for the different materials, and placing them as well as the theoretical differential cross-section into a plot:|Differential Cross-Section Offset]]==
−
! x<sub>f</sub>
 
−
! y<sub>f</sub>
 
−
! z<sub>f</sub>
 
−
! KE<sub>m</sub>
 
−
! Px<sub>m</sub>
 
−
! Py<sub>m</sub>
 
−
! Pz<sub>m</sub>
 
−
! x<sub>m</sub>
 
−
! y<sub>m</sub>
 
−
! z<sub>m</sub>
 
−
|-
 
−
| 11000
 
−
| 0
 
−
| 0
 
−
| 11000.5
 
−
| 0
 
−
| 0
 
−
| -510
 
−
| 10999.1
 
−
| 0.433025
 
−
| -0.858867
 
−
| 10999.6
 
−
| 0
 
−
| 0
 
−
| -509.276
 
−
| 0.905324
 
−
| -0.433025
 
−
| 0.858867
 
−
| 0.905366
 
−
| 0
 
−
| 0
 
−
| -509.276
 
−
|}
 
  
−
''Changing the code for the '''total Energy to <math>E=(p_1^2+m_1^2)^{1/2}</math>''' in the lab frame gives''
+
[[File:Adjusted_MollerXSect_NH3.png‎|frame|center|alt=Theoretical and Simulated Moller Differential Cross-Section in Center of Mass Frame Frame|'''Figure 5c:''' The theoretical and simulated Moller electron differential cross-section for an incident 11 GeV(Lab) electron in the Center of Mass frame of reference for NH3 target.  The theoretical differential cross-section has been adjusted to account for the 10 electrons within NH3.]]
  
−
[[File:FnlMomCM_new.png]][[File:MolMomCM_new.png]]
+
[[ROOT Macro to read LUND files and make plots]]
  
−
==Angular Distribution in the Lab Frame==   
 
  
−
[[File:FnlTheta.png]][[File:MolTheta.png]]
+
<center>[[File:LUND_MolMomCM.png]][[File:LUND_MolThetaCM.png]]</center>
  
  
−
==Angular Distribution in the Center of Mass Frame==
+
<center>[[File:LUND_MolMomLab.png]][[File:LUND_MolThetaLab.png]]</center>
  
−
[[File:FnlThetaCM.png]][[File:MolThetaCM.png]]
 
  
−
=='''[[Comparing experimental vs. theoretical for Møller differential cross section]]''' 11GeV==
+
Run the above theta and E distribution of Mollers through GEMC with and without Solenoid on.  Determine the Theta and E range of Mollers that enter the detector.
  
  
−
Using the equation from [1]
+
Scanning from 2MeV to 5500MeV, and 0 to 36 degrees in Theta.
  
−
<center><math>\frac{d\sigma}{d\Omega}=\frac{ e^4 }{8E^2}\left \{\frac{1+cos^4\frac{\theta}{2}}{sin^4\frac{\theta}{2}}+\frac{1+sin^4\frac{\theta}{2}}{cos^4\frac{\theta}{2}}+\frac{2}{sin^2\frac{\theta}{2}cos^2\frac{\theta}{2}} \right \}</math></center>
+
For Solenoid on with 5T:
  
 +
<pre>
 +
<gcard>
  
−
<center>where <math>\alpha=\frac{e^2}{\hbar c}\quad with\quad \hbar = c =1</math></center>
+
        <detector name="../../../../../clas12/fc/forwardCarriage" factory="TEXT" variation="original"/>
 +
        <detector name="../../../../../clas12/dc/dc"            factory="TEXT" variation="original"/>
 +
        <detector name="../../../../../clas12/ec/ec"            factory="TEXT" variation="original"/>
 +
        <detector name="../../../../../clas12/ctof/ctof"            factory="TEXT" variation="original"/>
 +
        <detector name="../../../../../clas12/ftof/ftof"            factory="TEXT" variation="original"/>
 +
        <detector name="../../../../../clas12/htcc/htcc"            factory="TEXT" variation="original"/>
 +
        <detector name="../../../../../clas12/pcal/pcal"            factory="TEXT" variation="original"/>
 +
        <option name="BEAM_P"  value="e-, 2.800*GeV, 18.0*deg, 10*deg"/>
 +
        <option name="SPREAD_P" value="2.798*GeV, 18*deg, 180*deg"/>
 +
        <option name="SCALE_FIELD" value="clas12-torus-big, -1.0"/>
 +
        <option name="HALL_FIELD"  value="clas12-solenoid"/>
 +
        <option name="SCALE_FIELD" value="clas12-solenoid, 1.0"/>
 +
        <option name="OUTPUT" value="evio,eg12.ev"/>
  
 +
</gcard>
  
−
This can be simplified to the form
+
</pre>
  
 +
Using the standard commands for gemc
  
−
<center><math>\frac{d\sigma}{d\Omega}=\frac{ \alpha^2 }{4E^2}\frac{ (3+cos^2\theta)^2}{sin^4\theta}</math></center>
+
<pre>
 +
gemc -USE_GUI=0 -N=1000 eg12_sol.gcard
 +
~/src/CLAS/coatjava-1.0/bin/clas12-reconstruction -i eg12.ev -config DCHB::torus=-1.0 -config DCHB::solenoid=1.0 -config DCTB::kalman=true -o eg12_rec.ev -s DCHB:DCTB:EC:FTOF:EB
 +
~/src/CLAS/coatjava-1.0/bin/run-groovy Analysis.groovy eg12_rec.0.evio
 +
</pre>
  
−
Plugging in the values expected for a scattering electron:
 
  
 +
Checking for a reconstructed particle that undergoes a phi shift where the 1st column is energy and the 2nd the scattering angle theta:
 +
<pre>
 +
For Energy:
 +
awk 'NR == 1 {line =$0; min =$2} NR >1 && $2 < min {line =$0; min = $2} END{print line}' Energy_Phi_Shift.dat
 +
289    0.6624017631112946      33.37507824033966      -179.63657653407975    0.7254709      29.696417      -177.79057      473.36051689004984      11.978802748439216      -129.55774724876173
  
  
 +
awk 'NR == 1 {line =$0; max =$2} NR >1 && $2 > max {line =$0; max = $2} END{print line}' Energy_Phi_Shift.dat
 +
978    5.584765946130235      24.90893565820338      -170.69784116534063    5.593401        24.90894        -170.65994      472.16552666546283      23.31807917059094      -165.11125601370114
  
−
<center><math>\alpha ^2=5.3279\times 10^{-5}</math></center>
+
For Theta:
 +
awk 'NR == 1 {line =$0; min =$3} NR >1 && $3 < min {line =$0; min = $3} END{print line}' Energy_Phi_Shift.dat
 +
12      4.83485521395583        10.577021312967325      -50.86708775351051      4.8205996      10.617784      -50.895683      491.627055439108        5.9032309421001985      -43.82964507576243
  
 +
awk 'NR == 1 {line =$0; max =$3} NR >1 && $3 > max {line =$0; max = $3} END{print line}' Energy_Phi_Shift.dat
 +
187    1.3382869250001856      35.63598792463312      29.887530073265214      1.3481133      35.449417      30.009071      472.455052447561        19.034043420497742      55.20328358414997
 +
</pre>
  
−
<center><math>E\approx 53 MeV</math></center>
 
  
 +
Similarly for 0T:
 +
<pre>
 +
For Energy:
 +
awk 'NR == 1 {line =$0; min =$2} NR >1 && $2 < min {line =$0; min = $2} END{print line}' Energy_Phi_Shift.dat
 +
148    0.36418038435234207    33.68296595663359      -175.89942431595827    0.35383263      51.743824      -39.45801      469.5694572319308      24.353383233947522      -176.27025218702502
  
−
Using unit analysis on the term outside the parantheses, we find that the differential cross section for an electron at this momentum should be around
 
  
−
<center><math>\frac{5.3279\times 10^{-5}}{4\times 2.81\times 10^{15}eV^2}=4.74\times 10^{-21} eV^{-2}=\frac{4.74\times 10^{-21}}{1eV^2}\times \frac{1\times 10^{18}eV^2 }{1\ GeV^2}=\frac{.0047}{GeV^2}</math></center>
+
awk 'NR == 1 {line =$0; max =$2} NR >1 && $2 > max {line =$0; max = $2} END{print line}' Energy_Phi_Shift.dat
 +
818    5.5278794590742235      12.937136966282836      -43.35663621477178      5.539351        12.95216        -49.09295      484.8800252169308      8.27731670021694        -43.245753766203364
  
−
Using the conversion of
+
For Theta:
 +
awk 'NR == 1 {line =$0; min =$3} NR >1 && $3 < min {line =$0; min = $3} END{print line}' Energy_Phi_Shift.dat
 +
559    4.909449160222199      9.918634647646794      0.06548256930681198    4.914272        9.938521        -5.861595      492.1448533455858      7.501204563534799      -0.006721611135017764
  
 +
awk 'NR == 1 {line =$0; max =$3} NR >1 && $3 > max {line =$0; max = $3} END{print line}' Energy_Phi_Shift.dat
 +
326    1.272966353429713      35.731680814303196      85.3173707349696        1.2830343      38.27654        58.368687      483.4835073848272      3.950855595379657      83.87603767806992
 +
</pre>
  
−
<center><math>\frac{1}{1GeV^2}=.3894 mb</math></center>
+
=Reconstruction of Moller Events=
  
 +
==[[DV_Creating_LUND_Files|The LUND format]]==
  
−
<center><math>\frac{1\ GeV^{-2}}{.3894\ mb}=\frac{.0047\ GeV^{-2}}{x\ mb}</math></center>
+
==[[DV_Running_LUND_for_Moller_Distribution|Writing LUND files]]==
  
−
We find that the differential cross section scale is <math>\frac{d\sigma}{d\Omega}\approx 1.8\times 10^{-3}mb=1.8\mu b</math>
+
==[[DV_Running_GEMC|Running GEMC]]==
  
 +
==[[DV_Analyze_Recon|Phi Shift observation using DC hit Reconstruction Data]]==
  
 +
=Gcard creation defining energy and angle range of electrons=
 +
==[[Modified gcards]]==
  
−
Converting the number of electrons to barns,
+
=Effects of Solenoid on Electrons=
 +
==[[Results for known Moller events|Results for defined distribution in Solenoid Fields]]==
  
−
:::::<math>L=\frac{i_{scattered}}{\sigma} \approx i_{scattered}\times \rho_{target}\times l_{target}</math>
+
==[[Results for Random Spread of Energy and angle theta in the Lab frame]]==
  
 +
=Cover Full Solid Angle of Detector=
  
−
where ρ<sub>target</sub> is the density of the target material, l<sub>target</sub> is the length of the target, and i<sub>scattered</sub> is the number of incident particles scattered.
+
==Using GEANT simulation data==
 +
===[[Calculations of 4-momentum components]]===
  
 +
===[[Alter Phi Angles]]===
  
−
:::::<math>\rho_{target}\times l_{target}=\frac{70.85 kg}{1 m^3}\times \frac{1 mole}{2.02 g} \times \frac{1000g}{1 kg} \times \frac{6\times10^{23} atoms}{1 mole} \times \frac{1m^3}{(100 cm)^3} \times \frac{1 cm}{ } \times \frac{10^{-24} cm^{-2}}{barn} =2.10\times 10^{2} barns</math>
+
===[[Check Differential Cross-Section]]===
  
  
−
:::::<math>\frac{1}{\rho_{target}\times l_{target} \times 4\times 10^7}=1.19\times 10^{-6} barns</math>
 
  
−
[[File:FnlThetaCM.png]][[File:Theory_new.png]]
 
  
 +
==Detector Occupancy==
  
−
Combining these plots, and rescaling the Final Theta in the Center of Mass for micro-barns, we find
+
clas12->Draw("Detector.wire:Detector.layer>>(7,1,7,120,0,120)","Detector.superlayer<3","colz")
  
 +
===[[gcard settings for daughter and procID|Gcard settings]]===
  
 +
===[[Verfication of Mother/Daughter Occupancy]]===
  
−
<center>[[File:XSect_new_zoom.png]]</center>
+
===[[Benchmark GEMC Occupancy Prediction for 11GeV Electron Beam with 0T Solenoid for LH2]]===
  
−
=Step 2=
 
  
−
Replace the LH2 target with an NH3 target and compare with LH2 target.
+
===[[Setup for Batch Job With Varying Experimental CLAS12 Quantities]]===
 +
===[[Run_in_GEMC]]===
 +
===[[Center_of_Mass_for_Stationary_Target]]===
  
 +
===[[Run Occupancy for Sector 1 DC hits]]===
 +
 
 +
===[[Wire_angle_correspondance]]===
 +
===[[Isotropic Weighted Moller Distribution in GEMC]]===
  
−
[[File:FnlMomNH3.png]][[File:MolMomNH3.png]]
+
=Papers used=
  
−
The Moller Momentum plot for higher momenta run to increase the number of values
+
[1]Farrukh Azfar's Derivation of Moller Scattering
  
−
[[File:Full_MolMom.png]]
+
:::[[File:FarrukAzfarMollerScatter.pdf]]
  
 +
A polarized target for the CLAS detector
  
 +
:::[[File:PHY02-33.pdf‎]]
  
−
[[File:FnlMomNH3CM.png]][[File:MolMomNH3CM.png]]
+
An investigation of the spin structure of the proton in deep inelastic scattering of polarized muons on polarized protons
  
 +
:::[[:File:1819.pdf]]
  
−
[[File:FnlThetaNH3.png]][[File:MolThetaNH3.png]]
+
==QED Radiative Corrections to Low-Energy Moller and Bhabha Scattering==
 +
http://arxiv.org/abs/1602.07609
  
 +
[[File:ChangingRates_S1_PhiThetaHits.png | 600 px]]
  
−
[[File:FnlThetaNH3CM.png]][[File:MolThetaNH3CM.png]]
+
[[File:S1_50nA_PrimaryElectronSigmasWeightedRates.png | 600 px]]
  
 +
[[File:S1_PhiThetaGammaHits.png | 600 px]]
  
  
 +
[[File:HitMakeUp.png]]
  
−
==LH2 Vs. NH3==
 
  
 +
[[File:S1_50nA_PrimaryElectronSigmasWeightedRates_Full.png | 600 px]]
  
−
:::::<math>L=\frac{870 kg}{1 m^3}\times \frac{1 mole}{17.03 g} \times \frac{1000g}{1 kg} \times \frac{6\times10^{23} atoms}{1 mole} \times \frac{1cm}{100 cm} \times \frac{1 m}{ } \times \frac{10^{-23} m^2}{barn} =2.10\times 10^{-2} barns</math>
+
[[File:ComparingOppositeFields_S1_PhiThetaHits.png | 800 px]]
  
−
[[File:DualFnlMom.png]][[File:DualMolMom.png]]
 
  
 +
[[File:ChangingSolenoidRates_wo_Magnets.png|800 px]]
  
−
[[File:DualFnlTheta.png]][[File:DualMolTheta.png]]
 
  
−
===Figure out the offset===
+
[[File:ComparingDCcomponents_S1_PhiThetaHits.png| 800 px]]
  
−
Rerunning the GEANT simulation for a target of solo atoms of Carbon 12, with 4<sup>10</sup> incident 11GeV electrons
 
  
  
−
[[File:3setsMom.png]][[File:3targets.png]]
+
[[File:ComparingDCEndplates_S1_PhiThetaHits.png | 800 px]]
  
−
Density of target material:
 
  
−
C=2.26 g/cm<sup>3</sup>
+
[[File:ComparingMagnetComponents_S1_PhiThetaHits.png| 800 px]]
  
−
NH3=.86g/cm<sup>3</sup>
+
[[File:S1_PhiThetaGammaHits_Full.png | 600 px]]
  
−
LH2=.07g/cm<sup>3</sup>
 
  
−
Altering the density of LH2 to be .86g/cm<sup>3</sup> we find
 
  
−
[[File:MolThetaMod4.png]]
 
  
−
=Step 3=
+
Tomography
  
−
Determine impact of Solenoid magnet on Moller events
+
[[File:S1_PhiThetaGammaVertex_wo_MagnetComponents.png | 600 px]]
  
−
=Papers used=
 
  
−
[1]Farrukh Azfar's Derivation of Moller Scattering
+
=GEANT4 Simulation of Lead Conic Moller Shield=
 +
==[[Lead Shield Cone]]==
  
−
:::[[File:FarrukAzfarMollerScatter.pdf]]
+
====OLD====
 +
{| class="wikitable"
 +
|+ FTOn from Forward Vertex
 +
! 50nA
 +
! S1R1 2ndryMoller e- rate
 +
! S1R1 2ndryMoller gamma rate
 +
! S1R1 2ndryMoller particle rate
 +
! Effective Shield Rate
 +
|-
 +
! R1_36_38_R2_36_38
 +
| ?
 +
| ?
 +
| ?
 +
| ?
  
−
A polarized target for the CLAS detector
+
|}
 +
{| class="wikitable"
 +
|+ OLD! FTOn from 0,0,0 Vertex
 +
! 50nA
 +
! S1R1 2ndryMoller e- rate
 +
! S1R1 2ndryMoller gamma rate
 +
! S1R1 2ndryMoller particle rate
 +
! Effective Shield Rate
 +
|-
 +
! R1_36_38_R2_36_38
 +
| 405 Hz
 +
| 15480 Hz
 +
| 160 Hz
 +
| ?
 +
|-
 +
! R1_36_38_R2_50_52
 +
| 470 Hz
 +
| 15227 Hz
 +
| 146 Hz
 +
| ?
 +
|-
 +
! R1_36_38_R2_70_72
 +
| 461 Hz
 +
| 15045 Hz
 +
| 150 Hz
 +
| ?
 +
|-
 +
! R1_36_38_R2_75_77
 +
| 372 Hz
 +
| 14916 Hz
 +
| 130 Hz
 +
| ?
 +
|-
 +
! R1_36_38_R2_80_82
 +
| 376 Hz
 +
| 14995 Hz
 +
| 109 Hz
 +
| ?
 +
|-
 +
! R1_36_38_R2_90_92
 +
| 413 Hz
 +
| 14580 Hz
 +
| 119 Hz
 +
| ?
 +
|-
 +
! R1_36_38_R2_95_97
 +
| 383 Hz
 +
| 14186 Hz
 +
| 117 Hz
 +
| ?
 +
|-
 +
! R1_36_38_R2_111_113
 +
| 447 Hz
 +
| 14196 Hz
 +
| 109 Hz
 +
| ?
 +
|-
 +
! R1_36_38_R2_116_118
 +
| 420 Hz
 +
| 14167 Hz
 +
| 144 Hz
 +
| ?
 +
|-
 +
! R1_36_38_R2_121_123
 +
| 389 Hz
 +
| 14251 Hz
 +
| 117 Hz
 +
| ?
 +
|-
 +
! R1_74_76_R2_151_153
 +
| 492 Hz
 +
| 14280 Hz
 +
| 110 Hz
 +
| ?
 +
|-
 +
! R1_36_38_R2_500_503
 +
| 1000 Hz
 +
| 18363 Hz
 +
| 120 Hz
 +
| ?
 +
|}
  
−
:::[[File:PHY02-33.pdf‎]]
+
{| class="wikitable"
 +
|+ FTOn from (0,0,0) Vertex w/o FT
 +
! 50nA
 +
! S1R1 2ndryMoller e- rate
 +
! S1R1 2ndryMoller gamma rate
 +
! S1R1 2ndryMoller particle rate
 +
! Effective Shield Rate
 +
|-
 +
! R1_0_524.0_R2_0_1034.47
 +
| ?
 +
| ?
 +
| ?
 +
| ?
  
−
An investigation of the spin structure of the proton in deep inelastic scattering of polarized muons on polarized protons
+
|}
  
−
:::[[:File:1819.pdf]]
+
{| class="wikitable"
 +
|+ FTOn from Forward Vertex
 +
! 50nA
 +
! S1R1 2ndryMoller e- rate
 +
! S1R1 2ndryMoller gamma rate
 +
! S1R1 2ndryMoller particle rate
 +
! Effective Shield Rate
 +
|-
 +
! R1_36_38_R2_36_38
 +
| ?
 +
| ?
 +
| ?
 +
| ?
  
−
==QED Radiative Corrections to Low-Energy Moller and Bhabha Scattering==
+
|}
−
http://arxiv.org/abs/1602.07609
 
  
−
=Moller Track Reconstruction=
 
  
−
[[DV_MollerTrackRecon]]
+
[[VanWasshenova_Thesis]]
  
 
[[EG12]]
 
[[EG12]]

Latest revision as of 18:03, 13 January 2019

need to insert moller shielding into card after moller LUND file is created. (see clas12/beamline)

Simulating the Moller scattering background for EG12

Docker

Set up Docker Container

Moller Differential Cross-Section

GEANT4 Simulation of Moller Events

Simulation Setup

Use GEANT4 via GEMC to estimate the Moller background for electron scattering experiments in JLab's Hall B. The first step towards this goal is to use GEANT4 without the GEMC infrastructure to create event (LUND) files that will be used as input events for GEMC.

Benchmark GEANT4's Moller scattering prediction with the theoretical cross section using LH2

Comparison of simulation vs. the theoretical Møller differential cross section using 11 GeV electrons impinging LH2

Converting the number of scattered electrons per scattering angle theta to a differential cross-section in barns.

Experimental and Theoretical Moller Differential Cross-Section in Center of Mass Frame Frame
Figure 5c: The experimental and theoretical Moller electron differential cross-section for an incident 11 GeV(Lab) electron in the Center of Mass frame of reference.

Change to a NH3 Target

Replacing the LH2 target with an NH3 target

Benchmark GEANT4's Moller scattering prediction with the theoretical cross section using NH3

Comparison of simulation vs. the theoretical Møller differential cross section using 11 GeV electrons impinging NH3

Converting the number of scattered electrons per scattering angle theta to a differential cross-section in barns.

Theoretical and Simulated Moller Differential Cross-Section in Center of Mass Frame Frame
Figure 5c: The theoretical and simulated Moller electron differential cross-section for an incident 11 GeV(Lab) electron in the Center of Mass frame of reference for NH3 target.

LH2 Vs. NH3

Benchmark GEANT4's Moller scattering prediction for NH3 and LH2

Effects Due to Target Material

Target Density

Atomic Mass and Electron Number Effects

Differential Cross-Section Offset

Theoretical and Simulated Moller Differential Cross-Section in Center of Mass Frame Frame
Figure 5c: The theoretical and simulated Moller electron differential cross-section for an incident 11 GeV(Lab) electron in the Center of Mass frame of reference for NH3 target. The theoretical differential cross-section has been adjusted to account for the 10 electrons within NH3.

ROOT Macro to read LUND files and make plots


LUND MolMomCM.pngLUND MolThetaCM.png


LUND MolMomLab.pngLUND MolThetaLab.png


Run the above theta and E distribution of Mollers through GEMC with and without Solenoid on.  Determine the Theta and E range of Mollers that enter the detector.


Scanning from 2MeV to 5500MeV, and 0 to 36 degrees in Theta.

For Solenoid on with 5T: 

<gcard>

        <detector name="../../../../../clas12/fc/forwardCarriage" factory="TEXT" variation="original"/>
        <detector name="../../../../../clas12/dc/dc"            factory="TEXT" variation="original"/>
        <detector name="../../../../../clas12/ec/ec"            factory="TEXT" variation="original"/>
        <detector name="../../../../../clas12/ctof/ctof"            factory="TEXT" variation="original"/>
        <detector name="../../../../../clas12/ftof/ftof"            factory="TEXT" variation="original"/>
        <detector name="../../../../../clas12/htcc/htcc"            factory="TEXT" variation="original"/>
        <detector name="../../../../../clas12/pcal/pcal"            factory="TEXT" variation="original"/>
        <option name="BEAM_P"   value="e-, 2.800*GeV, 18.0*deg, 10*deg"/>
        <option name="SPREAD_P" value="2.798*GeV, 18*deg, 180*deg"/>
        <option name="SCALE_FIELD" value="clas12-torus-big, -1.0"/>
        <option name="HALL_FIELD"  value="clas12-solenoid"/>
        <option name="SCALE_FIELD" value="clas12-solenoid, 1.0"/>
        <option name="OUTPUT" value="evio,eg12.ev"/>

</gcard>

Using the standard commands for gemc 

gemc -USE_GUI=0 -N=1000 eg12_sol.gcard
~/src/CLAS/coatjava-1.0/bin/clas12-reconstruction -i eg12.ev -config DCHB::torus=-1.0 -config DCHB::solenoid=1.0 -config DCTB::kalman=true -o eg12_rec.ev -s DCHB:DCTB:EC:FTOF:EB
~/src/CLAS/coatjava-1.0/bin/run-groovy Analysis.groovy eg12_rec.0.evio


Checking for a reconstructed particle that undergoes a phi shift where the 1st column is energy and the 2nd the scattering angle theta: 

For Energy:
awk 'NR == 1 {line =$0; min =$2} NR >1 && $2 < min {line =$0; min = $2} END{print line}' Energy_Phi_Shift.dat
289     0.6624017631112946      33.37507824033966       -179.63657653407975     0.7254709       29.696417       -177.79057      473.36051689004984      11.978802748439216      -129.55774724876173


awk 'NR == 1 {line =$0; max =$2} NR >1 && $2 > max {line =$0; max = $2} END{print line}' Energy_Phi_Shift.dat
978     5.584765946130235       24.90893565820338       -170.69784116534063     5.593401        24.90894        -170.65994      472.16552666546283      23.31807917059094       -165.11125601370114

For Theta:
awk 'NR == 1 {line =$0; min =$3} NR >1 && $3 < min {line =$0; min = $3} END{print line}' Energy_Phi_Shift.dat
12      4.83485521395583        10.577021312967325      -50.86708775351051      4.8205996       10.617784       -50.895683      491.627055439108        5.9032309421001985      -43.82964507576243

awk 'NR == 1 {line =$0; max =$3} NR >1 && $3 > max {line =$0; max = $3} END{print line}' Energy_Phi_Shift.dat
187     1.3382869250001856      35.63598792463312       29.887530073265214      1.3481133       35.449417       30.009071       472.455052447561        19.034043420497742      55.20328358414997


Similarly for 0T: 

For Energy:
awk 'NR == 1 {line =$0; min =$2} NR >1 && $2 < min {line =$0; min = $2} END{print line}' Energy_Phi_Shift.dat
148     0.36418038435234207     33.68296595663359       -175.89942431595827     0.35383263      51.743824       -39.45801       469.5694572319308       24.353383233947522      -176.27025218702502


awk 'NR == 1 {line =$0; max =$2} NR >1 && $2 > max {line =$0; max = $2} END{print line}' Energy_Phi_Shift.dat
818     5.5278794590742235      12.937136966282836      -43.35663621477178      5.539351        12.95216        -49.09295       484.8800252169308       8.27731670021694        -43.245753766203364

For Theta:
awk 'NR == 1 {line =$0; min =$3} NR >1 && $3 < min {line =$0; min = $3} END{print line}' Energy_Phi_Shift.dat
559     4.909449160222199       9.918634647646794       0.06548256930681198     4.914272        9.938521        -5.861595       492.1448533455858       7.501204563534799       -0.006721611135017764

awk 'NR == 1 {line =$0; max =$3} NR >1 && $3 > max {line =$0; max = $3} END{print line}' Energy_Phi_Shift.dat
326     1.272966353429713       35.731680814303196      85.3173707349696        1.2830343       38.27654        58.368687       483.4835073848272       3.950855595379657       83.87603767806992

Reconstruction of Moller Events

The LUND format

Writing LUND files

Running GEMC

Phi Shift observation using DC hit Reconstruction Data

Gcard creation defining energy and angle range of electrons

Modified gcards

Effects of Solenoid on Electrons

Results for defined distribution in Solenoid Fields

Results for Random Spread of Energy and angle theta in the Lab frame

Cover Full Solid Angle of Detector

Using GEANT simulation data

Calculations of 4-momentum components

Alter Phi Angles

Check Differential Cross-Section

Detector Occupancy

clas12->Draw("Detector.wire:Detector.layer>>(7,1,7,120,0,120)","Detector.superlayer<3","colz")

Gcard settings

Verfication of Mother/Daughter Occupancy

Benchmark GEMC Occupancy Prediction for 11GeV Electron Beam with 0T Solenoid for LH2

Setup for Batch Job With Varying Experimental CLAS12 Quantities

Run_in_GEMC

Center_of_Mass_for_Stationary_Target

Run Occupancy for Sector 1 DC hits

Wire_angle_correspondance

Isotropic Weighted Moller Distribution in GEMC

Papers used

[1]Farrukh Azfar's Derivation of Moller Scattering

File:FarrukAzfarMollerScatter.pdf

A polarized target for the CLAS detector

File:PHY02-33.pdf

An investigation of the spin structure of the proton in deep inelastic scattering of polarized muons on polarized protons

File:1819.pdf

QED Radiative Corrections to Low-Energy Moller and Bhabha Scattering

http://arxiv.org/abs/1602.07609

ChangingRates S1 PhiThetaHits.png

S1 50nA PrimaryElectronSigmasWeightedRates.png

S1 PhiThetaGammaHits.png


HitMakeUp.png


S1 50nA PrimaryElectronSigmasWeightedRates Full.png

ComparingOppositeFields S1 PhiThetaHits.png


ChangingSolenoidRates wo Magnets.png


ComparingDCcomponents S1 PhiThetaHits.png


ComparingDCEndplates S1 PhiThetaHits.png


ComparingMagnetComponents S1 PhiThetaHits.png

S1 PhiThetaGammaHits Full.png



Tomography

S1 PhiThetaGammaVertex wo MagnetComponents.png


GEANT4 Simulation of Lead Conic Moller Shield

Lead Shield Cone

OLD

FTOn from Forward Vertex
50nA S1R1 2ndryMoller e- rate S1R1 2ndryMoller gamma rate S1R1 2ndryMoller particle rate Effective Shield Rate
R1_36_38_R2_36_38 ? ? ? ?
OLD! FTOn from 0,0,0 Vertex
50nA S1R1 2ndryMoller e- rate S1R1 2ndryMoller gamma rate S1R1 2ndryMoller particle rate Effective Shield Rate
R1_36_38_R2_36_38 405 Hz 15480 Hz 160 Hz ?
R1_36_38_R2_50_52 470 Hz 15227 Hz 146 Hz ?
R1_36_38_R2_70_72 461 Hz 15045 Hz 150 Hz ?
R1_36_38_R2_75_77 372 Hz 14916 Hz 130 Hz ?
R1_36_38_R2_80_82 376 Hz 14995 Hz 109 Hz ?
R1_36_38_R2_90_92 413 Hz 14580 Hz 119 Hz ?
R1_36_38_R2_95_97 383 Hz 14186 Hz 117 Hz ?
R1_36_38_R2_111_113 447 Hz 14196 Hz 109 Hz ?
R1_36_38_R2_116_118 420 Hz 14167 Hz 144 Hz ?
R1_36_38_R2_121_123 389 Hz 14251 Hz 117 Hz ?
R1_74_76_R2_151_153 492 Hz 14280 Hz 110 Hz ?
R1_36_38_R2_500_503 1000 Hz 18363 Hz 120 Hz ?
FTOn from (0,0,0) Vertex w/o FT
50nA S1R1 2ndryMoller e- rate S1R1 2ndryMoller gamma rate S1R1 2ndryMoller particle rate Effective Shield Rate
R1_0_524.0_R2_0_1034.47 ? ? ? ?
FTOn from Forward Vertex
50nA S1R1 2ndryMoller e- rate S1R1 2ndryMoller gamma rate S1R1 2ndryMoller particle rate Effective Shield Rate
R1_36_38_R2_36_38 ? ? ? ?


VanWasshenova_Thesis

EG12

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