Difference between revisions of "Mlr Summ TF"

From New IAC Wiki
Jump to navigation Jump to search
 
(124 intermediate revisions by 2 users not shown)
Line 7: Line 7:
  
  
−
https://wiki.iac.isu.edu/index.php/Converting_to_barns
+
As derived earlier, in the [[Differential_Cross-Section]] section
  
  
 +
In the Ultra-relativistic limit as <math> E \approx p</math>
  
−
<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>
+
 
 +
<center><math>\frac{d\sigma}{d\Omega}=\frac{\alpha ^2}{4E^{*2}\sin^4{\theta}}\left( \cos^4{\theta}+6\cos^2{\theta}+9\right)=\frac{\alpha ^2\left(3+\cos^2{\theta}\right)^2}{4E^{*2}\sin^4{\theta}} </math></center>
  
  
Line 29: Line 31:
  
 
[[File:MollerEThetaSigma_Full.png|frame|center|alt=Moller Electron Energy vs Angle Theta in Lab Frame|'''Figure 2:''' Using the theoretical differential cross section, the distribution of Moller electrons for a CM energy of approximately 53Mev can be distributed through the CM scattering angle Theta.  Using Lorentz transformations, these distributions can be transformed to the lab frame.  At around 60 degrees in the lab the Moller electron has an energy of close to 1 MeV.  Such a low energy does not allow the Moller electron to leave the constrains of the target where they are created.]]
 
[[File:MollerEThetaSigma_Full.png|frame|center|alt=Moller Electron Energy vs Angle Theta in Lab Frame|'''Figure 2:''' Using the theoretical differential cross section, the distribution of Moller electrons for a CM energy of approximately 53Mev can be distributed through the CM scattering angle Theta.  Using Lorentz transformations, these distributions can be transformed to the lab frame.  At around 60 degrees in the lab the Moller electron has an energy of close to 1 MeV.  Such a low energy does not allow the Moller electron to leave the constrains of the target where they are created.]]
 +
 +
Moller electron radius -vs- Momentum (Full solenoid and relativistic)
  
 
== Baseline==
 
== Baseline==
Line 41: Line 45:
  
  
−
[[File:ChangingRates_S1_PhiThetaHits_Full.png|600 px|frame|center|alt=Moller Electron Energy vs Angle Theta in Lab Frame|'''Figure 2:''' With the Torus strength at zero Telsa, the solenoid is varied to show the hits within the DC moving off the faces of R1.  These hits consist of primary Moller electrons, as well as secondary electrons and photons created by the Moller electrons.]]
+
[[File:ChangingRates_S1_PhiThetaHits_Full.png||200 px|frame|center|alt=Moller Electron Energy vs Angle Theta in Lab Frame|'''Figure 2:''' With the Torus strength at zero Telsa, the solenoid is varied to show the hits within the DC moving off the faces of R1.  These hits consist of primary Moller electrons, as well as secondary electrons and photons created by the Moller electrons.]]
 +
 
 +
 
 +
As the Solenoid field strength increases, the Moller electrons are forced to into a helical path of decreasing radius, effectively "rotating" off the DC face.  The relative value of the field changes the direction field, which in turn causes slightly more hits to be deposited on one side versus the other.  This effect is only noticeable in that the neighboring sectors to S1 were not simulated.
 +
 
 +
 
 +
[[File:CompareOppositeFieldsFULL_S1_PhiThetaHits.png|200 px|frame|center|alt=Moller Electron Energy vs Angle Theta in Lab Frame|'''Figure 2:''' The effect of the sign of the solenoid magnetic field is apparent when neighboring sectors are not simulated.]]
 +
 
 +
 
 +
 
 +
However, as the field reaches maximum, there are still particles which are found at higher values of <math>\theta</math> that would have been expected to have remained after the effects of the Solenoid.  To understand the causes of this phenomena, the hits on Region 1 can be broken into the most common types of particles that are detected; Primary Moller electrons and secondary electrons and photons caused by the Moller electron.  Looking more closely at this particle makeup as the solenoid field is increased, we can see that the ratio of primary electrons to total hits decreases while the ratio of photons to total hits increases.
 +
 
 +
 
 +
 
 +
[[File:DC_MAG_rates_barPlot.png|600 px|frame|center|alt=Moller Electron Energy vs Angle Theta in Lab Frame|'''Figure 2:''' The  rate of primary Moller electron  traversing S1R1 decreases as the solenoid field strength is increased.]]
  
  
−
As the Solenoid field strength increases, the Moller electrons are forced to into a helical path of decreasing radius, effectively "rotating" off the DC face.  However, as the field reaches maximum, there are still particles which are found at higher values of <math>/theta</math> that would have been expected to have remained after the effects of the Solenoid.  To understand the causes of this phenomena, the hits on Region 1 can be broken into the most common types of particles that are detected; Primary Moller electrons and secondary electrons and photons caused by the Moller electron.  Looking more closely at this particle makeup as the solenoid field is increased, we can see that the number of electrons decrease while the photons increase.
 
  
−
[[File:HitMakeUp.png]]
 
  
  
−
[[File:ComparingOppositeFields_S1_PhiThetaHits.png | 800 px]]
 
  
 
====Without Magnet Components====
 
====Without Magnet Components====
 +
To examine the possibility that scattering is the cause of the noise, the simulation is further simplified by removing the magnetic components stored in the CAD directory.
 +
 +
 +
 +
[[File:ComparingMagnetComponentsFULL_S1_PhiThetaHits.png|600 px|frame|center|alt=Moller Electron Energy vs Angle Theta in Lab Frame|'''Figure 2:''' With the Torus strength at zero Telsa, the solenoid is at full strength and the magnet components in the CAD directory are removed.  Due to scattering effects, the rate for 50nA is reduced by a factor of almost 20.]]
 +
 +
 +
 +
 +
 +
 +
 +
 +
 +
 +
To effectively determine the cause of the remaining particles in S1R1 the hit particles' vertex points can be recorded producing a tomography plot.  A changing field is still useful in that the lack of number of hits at high solenoid field strength would make determining the physical cause difficult.
 +
 +
=====Photons Hits in R1=====
 +
 +
[[File:Screen_ShotMollerGammaPhiThetaBins.png]]
 +
 +
[[Merging background hits]]
 +
 +
=====Secondary Electron Hits in R1=====
 +
 +
 +
=====Primary Moller Electron Hits in R1=====
 +
 +
 +
[[File:ComponentStudy.png]]
  
−
[[File:ComparingMagnetComponents_S1_PhiThetaHits.png| 800 px]]
+
==CLAS12 Conditions==
  
 +
  Summarize with picture photo rates -vs- change and location of photons
  
−
[[File:ChangingSolenoidRates_wo_Magnets.png|800 px]]
 
  
−
=====With Only S1R1 DC=====
+
  Summarize secondary moller electron rate location
  
  
 +
===[[Determining and Verify Shield Limits]]===
  
−
What are the particles in the R1S1 only plot and where are they from
+
===FTOn ShieldIn===
  
−
[[File:ComparingDCcomponents_S1_PhiThetaHits.png| 800 px]]
+
For the Moller electron,
  
 +
[[File:FTOn_ShieldIn_S1R1Moller_withTomography.png]]
  
  
−
[[File:ComparingDCEndplates_S1_PhiThetaHits.png | 800 px]]
+
For the scattered electron, there are no secondary hits.
  
−
===Moller Electron Events(1st hits)===
+
===FTOff ShieldIn===
  
−
[[File:S1_50nA_PrimaryElectronSigmasWeightedRates_Full.png | 600 px]]
+
For secondary hits from the Moller electron
  
−
===Photons Hits in R1===
+
[[File:FTOff_ShieldIn_S1R1Moller_withTomography.png]]
−
[[File:S1_PhiThetaGammaHits_Full.png | 600 px]]
 
  
 +
===FTOn ShieldOut===
  
 +
[[File:FTOn_ShieldOut_S1R1Moller_withTomography.png]]
  
 +
===FTOff ShieldOut===
  
−
Tomography
+
[[File:FTOff_ShieldOut_S1R1Moller_withTomography.png]]
 +
==New Cone==
  
−
[[File:S1_PhiThetaGammaVertex_wo_MagnetComponents.png | 600 px]]
 
  
 +
===FTOn===
 +
From beamline text file
 +
<pre>
 +
1589.27-238.8=1350.47
 +
</pre>
  
 +
<pre>
 +
PbCylinder  |                root  |        Pb pipe on beamline  |                          0*mm 0.0*mm 1350.47*mm  |                                  0 0 0  | 999966  |                Cons  |                          34*mm 36*mm 111.2*mm 113.2*mm 441.3*mm 0.0*deg 360*deg  |          beamline_w  |                  no  |    1  |    1  |    1  |  1  |  1  |                  no  |                  no  |                                      no
 +
</pre>
  
 +
'''At Standard Vertex Position:'''
  
−
[[File:ComponentStudy.png]]
+
 
 +
High Cone Position:
 +
 
 +
<math>1350.47+441.3=1791.77\ mm</math>
 +
 
 +
<math>\theta_{high}=\arctan \left( \frac{113.2}{1791.77} \right)=3.61^{\circ}</math>
 +
 
 +
 
 +
Low Cone Position:
 +
 
 +
<math>1350.47-441.3=909.17\ mm</math>
 +
 
 +
<math>\theta_{low}=\arctan \left( \frac{113.2}{909.17} \right)=2.39^{\circ}</math>
 +
 
 +
====[[standard_R1_36_38_R2_111_113]]====
 +
 
 +
'''At forward Vertex Position:''' ''(subtract 40mm from standard vertex distance)''
 +
 
 +
High Cone Position:
 +
 
 +
<math>1791.77-40=1751.77\ mm</math>
 +
 
 +
<math>\theta_{high}=\arctan \left( \frac{113.2}{1751.77} \right)=3.69^{\circ}</math>
 +
 
 +
 
 +
Low Cone Position:
 +
 
 +
<math>909.17-40=869.17\ mm</math>
 +
 
 +
<math>\theta_{low}=\arctan \left( \frac{113.2}{869.17} \right)=2.5^{\circ}</math>
 +
 
 +
 
 +
<math>\rightarrow \theta_{high}=5^{\circ} \rightarrow 1751.77 \arctan 5^{\circ} = 153.26\ mm </math>
 +
 
 +
<math>\rightarrow \theta_{low}=5^{\circ} \rightarrow 869.17 \arctan 5^{\circ} = 76.04\ mm </math>
 +
 
 +
====[[standard_R1_74_76_R2_151_153]]====
 +
 
 +
 
 +
====Summary Tables====
 +
{| class="wikitable"
 +
|+ 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
 +
| 111 Hz
 +
| 10652 Hz
 +
| 37 Hz
 +
| ?
 +
|-
 +
! R1_36_38_R2_50_54
 +
| 108 Hz
 +
| 10668 Hz
 +
| 31 Hz
 +
| ?
 +
|-
 +
! R1_36_38_R2_70_72
 +
| 109 Hz
 +
| 11053 Hz
 +
| 45 Hz
 +
| ?
 +
|-
 +
! R1_36_38_R2_75_77
 +
|  Hz
 +
|  Hz
 +
|  Hz
 +
| ?
 +
|-
 +
! R1_36_38_R2_80_82
 +
|  Hz
 +
|  Hz
 +
|  Hz
 +
| ?
 +
|-
 +
! R1_36_38_R2_90_92
 +
|  Hz
 +
|  Hz
 +
|  Hz
 +
| ?
 +
|-
 +
! R1_36_38_R2_95_97
 +
|  Hz
 +
|  Hz
 +
|  Hz
 +
| ?
 +
|-
 +
! R1_36_38_R2_100_102
 +
|  Hz
 +
|  Hz
 +
|  Hz
 +
| ?
 +
|-
 +
! R1_36_38_R2_111_113
 +
|  Hz
 +
|  Hz
 +
|  Hz
 +
| ?
 +
|-
 +
! R1_36_38_R2_116_118
 +
|  Hz
 +
|  Hz
 +
|  Hz
 +
| ?
 +
|-
 +
! R1_36_38_R2_121_123
 +
|  Hz
 +
|  Hz
 +
|  Hz
 +
| ?
 +
|-
 +
! R1_74_76_R2_151_153
 +
|  Hz
 +
|  Hz
 +
|  Hz
 +
| ?
 +
|-
 +
! R1_36_38_R2_500_503
 +
| 150 Hz
 +
| 12097 Hz
 +
| 46 Hz
 +
| ?
 +
|}
 +
 
 +
{| 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
 +
| ?
 +
| ?
 +
| ?
 +
| ?
 +
 
 +
|}
 +
 
 +
==Moller Electrons below 5 degrees==
 +
[[File:ReallyFullMolThetaMomLabWeighted.png | 300 px]]
 +
 
 +
[[CLAS12_MollerDataTable_12-16-2018]]
  
 
== Moller events using an dual polarized target geometry with Raster==
 
== Moller events using an dual polarized target geometry with Raster==
Line 103: Line 307:
  
 
=Latest Stuff=
 
=Latest Stuff=
 +
 +
[[File:UnweightedOccupancy_need_to_fix.png]]
  
 
[[VanWasshenova_Thesis#Mlr_Summ_TF]]
 
[[VanWasshenova_Thesis#Mlr_Summ_TF]]
 +
 +
= References=
 +
 +
[https://misportal.jlab.org/mis/physics/clas12/viewFile.cfm/2016-006.pdf?documentId=32  CLASNOTE 2016-06 Moller shield simulations: comparison of the GEMC-optimized layout and the engineering design]

Latest revision as of 03:09, 11 April 2019

VanWasshenova_Thesis#Mlr_Summ_TF

Moller Summary

Scattering Xsect

As derived earlier, in the Differential_Cross-Section section


In the Ultra-relativistic limit as [math] E \approx p[/math]


[math]\frac{d\sigma}{d\Omega}=\frac{\alpha ^2}{4E^{*2}\sin^4{\theta}}\left( \cos^4{\theta}+6\cos^2{\theta}+9\right)=\frac{\alpha ^2\left(3+\cos^2{\theta}\right)^2}{4E^{*2}\sin^4{\theta}} [/math]





Theory Frame Moller CM Frame
Figure 3a: A plot of the number of Moller scattering angle theta in the center of mass frame versus the theoretical differential cross section. The width of the bins is 0.001 degrees for the angles in the center of mass frame corresponding to angles of 5 to 40 degrees in the lab frame. A weight has been assigned for each value in theta which will give the theoretical differential cross section when applied.
Theory Lab Frame Moller Frame
Figure 3b: A plot of the number of Moller scattering angle theta in the lab frame versus the theoretical differential cross section. The width of the bins is 0.5 degrees for the angles in the lab frame. A weight has been assigned for each value in theta which will give the theoretical differential cross section when applied.


Weight the E-vs-Theta plot with Xsect
Moller Electron Energy vs Angle Theta in Lab Frame
Figure 2: Using the theoretical differential cross section, the distribution of Moller electrons for a CM energy of approximately 53Mev can be distributed through the CM scattering angle Theta. Using Lorentz transformations, these distributions can be transformed to the lab frame. At around 60 degrees in the lab the Moller electron has an energy of close to 1 MeV. Such a low energy does not allow the Moller electron to leave the constrains of the target where they are created.
Moller electron radius -vs- Momentum (Full solenoid and relativistic)

Baseline

Moller events using an lH2 target geometry No Raster

DC hits -vs- Solenoid

Starting the clas12 Moller simulation with a simple configuration, most components downstream with respect to the drift chambers are taken out of the gcard file. The remaining components, the Drift Chamber (DC), the Solenoid, and the Magnetic Components (CAD) are all that remain as shown below. The Torus field is held at zero Tesla, and the Solenoid field strength is increased from 0 to it's max of 5T.


Moller Electron Energy vs Angle Theta in Lab Frame
Figure 2: With the Torus strength at zero Telsa, the solenoid is varied to show the hits within the DC moving off the faces of R1. These hits consist of primary Moller electrons, as well as secondary electrons and photons created by the Moller electrons.


As the Solenoid field strength increases, the Moller electrons are forced to into a helical path of decreasing radius, effectively "rotating" off the DC face. The relative value of the field changes the direction field, which in turn causes slightly more hits to be deposited on one side versus the other. This effect is only noticeable in that the neighboring sectors to S1 were not simulated.


Moller Electron Energy vs Angle Theta in Lab Frame
Figure 2: The effect of the sign of the solenoid magnetic field is apparent when neighboring sectors are not simulated.


However, as the field reaches maximum, there are still particles which are found at higher values of [math]\theta[/math] that would have been expected to have remained after the effects of the Solenoid. To understand the causes of this phenomena, the hits on Region 1 can be broken into the most common types of particles that are detected; Primary Moller electrons and secondary electrons and photons caused by the Moller electron. Looking more closely at this particle makeup as the solenoid field is increased, we can see that the ratio of primary electrons to total hits decreases while the ratio of photons to total hits increases.


Moller Electron Energy vs Angle Theta in Lab Frame
Figure 2: The rate of primary Moller electron traversing S1R1 decreases as the solenoid field strength is increased.




Without Magnet Components

To examine the possibility that scattering is the cause of the noise, the simulation is further simplified by removing the magnetic components stored in the CAD directory.


Moller Electron Energy vs Angle Theta in Lab Frame
Figure 2: With the Torus strength at zero Telsa, the solenoid is at full strength and the magnet components in the CAD directory are removed. Due to scattering effects, the rate for 50nA is reduced by a factor of almost 20.






To effectively determine the cause of the remaining particles in S1R1 the hit particles' vertex points can be recorded producing a tomography plot.  A changing field is still useful in that the lack of number of hits at high solenoid field strength would make determining the physical cause difficult.
Photons Hits in R1

Screen ShotMollerGammaPhiThetaBins.png

Merging background hits

Secondary Electron Hits in R1
Primary Moller Electron Hits in R1

ComponentStudy.png

CLAS12 Conditions

 Summarize with picture photo rates -vs- change and location of photons



  Summarize secondary moller electron rate location


Determining and Verify Shield Limits

FTOn ShieldIn

For the Moller electron,

FTOn ShieldIn S1R1Moller withTomography.png


For the scattered electron, there are no secondary hits.

FTOff ShieldIn

For secondary hits from the Moller electron

FTOff ShieldIn S1R1Moller withTomography.png

FTOn ShieldOut

FTOn ShieldOut S1R1Moller withTomography.png

FTOff ShieldOut

FTOff ShieldOut S1R1Moller withTomography.png

New Cone

FTOn

From beamline text file 

1589.27-238.8=1350.47

PbCylinder  |                root  |         Pb pipe on beamline  |                           0*mm 0.0*mm 1350.47*mm  |                                   0 0 0  | 999966   |                Cons  |                          34*mm 36*mm 111.2*mm 113.2*mm 441.3*mm 0.0*deg 360*deg  |          beamline_w  |                  no  |     1   |     1   |     1   |   1   |   1   |                  no  |                  no  |                                      no

At Standard Vertex Position:


High Cone Position:

[math]1350.47+441.3=1791.77\ mm[/math]

[math]\theta_{high}=\arctan \left( \frac{113.2}{1791.77} \right)=3.61^{\circ}[/math]


Low Cone Position:

[math]1350.47-441.3=909.17\ mm[/math]

[math]\theta_{low}=\arctan \left( \frac{113.2}{909.17} \right)=2.39^{\circ}[/math]

standard_R1_36_38_R2_111_113

At forward Vertex Position: (subtract 40mm from standard vertex distance)

High Cone Position:

[math]1791.77-40=1751.77\ mm[/math]

[math]\theta_{high}=\arctan \left( \frac{113.2}{1751.77} \right)=3.69^{\circ}[/math]


Low Cone Position:

[math]909.17-40=869.17\ mm[/math]

[math]\theta_{low}=\arctan \left( \frac{113.2}{869.17} \right)=2.5^{\circ}[/math]


[math]\rightarrow \theta_{high}=5^{\circ} \rightarrow 1751.77 \arctan 5^{\circ} = 153.26\ mm [/math]

[math]\rightarrow \theta_{low}=5^{\circ} \rightarrow 869.17 \arctan 5^{\circ} = 76.04\ mm [/math]

standard_R1_74_76_R2_151_153

Summary Tables

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_38 111 Hz 10652 Hz 37 Hz ?
R1_36_38_R2_50_54 108 Hz 10668 Hz 31 Hz ?
R1_36_38_R2_70_72 109 Hz 11053 Hz 45 Hz ?
R1_36_38_R2_75_77 Hz Hz Hz ?
R1_36_38_R2_80_82 Hz Hz Hz ?
R1_36_38_R2_90_92 Hz Hz Hz ?
R1_36_38_R2_95_97 Hz Hz Hz ?
R1_36_38_R2_100_102 Hz Hz Hz ?
R1_36_38_R2_111_113 Hz Hz Hz ?
R1_36_38_R2_116_118 Hz Hz Hz ?
R1_36_38_R2_121_123 Hz Hz Hz ?
R1_74_76_R2_151_153 Hz Hz Hz ?
R1_36_38_R2_500_503 150 Hz 12097 Hz 46 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 ? ? ? ?

Moller Electrons below 5 degrees

ReallyFullMolThetaMomLabWeighted.png

CLAS12_MollerDataTable_12-16-2018

Moller events using an dual polarized target geometry with Raster

Photon Hits in R1 when Raster size has radius of 0.2 cm

Moller rate -vs- length of a single taerget

0.5 cm radius -vs- Z

Target is a one 0.5 cm radius cylinder of length Z.

By how much does the moller rate change at full field ?

Latest Stuff

UnweightedOccupancy need to fix.png

VanWasshenova_Thesis#Mlr_Summ_TF

References

CLASNOTE 2016-06 Moller shield simulations: comparison of the GEMC-optimized layout and the engineering design

Retrieved from "https://wiki.iac.isu.edu/index.php?title=Mlr_Summ_TF&oldid=126103"