Difference between revisions of "DC hits to Moller XSection"

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Examing the CM Frame Theta angles which correspond to Lab frame angles within 5-40 degrees, for only on degree in Phi (0 degrees)
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=Verification using LUND and evio files=
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The LUND files are broken into 1000 events per file to produce manageable GEMC output file sizes.  The kinematics of these Moller events is shown fin Figure 1. 
  
[[File:TheoryXSect_MolThetaCM_5to40Lab.png]]
 
  
For each degree in Theta in the Lab frame, the correct kinematic variables are written to a LUND file 1000 times. These events are read from the evio file using
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[[File:MolMomCM_11_2.png |thumb | border | center |500 px |alt=Moller Momentum Center of Mass Frame |'''Figure 1a:''' A plot of Moller electron momentum in the center of mass frame.]][[File:MolTheteaCM_full.png |thumb | border | center |500 px |alt=Moller Theta Center of Mass |'''Figure 1b:'''A plot of Moller electron scattering angle theta in the center of mass frame.]]
  
 
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=[[DV_RunGroupC_Moller#DC_hits_to_Moller_XSection|back]]=
 
 
The Moller Scattering angle Theta is read from the evio file, and it's weight adjusted by dividing by the number it was multiplied by (1000) to give
 
 
 
[[File:MolThetaCMweighted_multiplied1000x.png]]
 
 
 
 
 
From the evio file, a histogram can be constructed that will only record the Moller events which result in hits in the drift chamber.  A hit for this setting is the
 
 
 
 
 
Plotting the Moller scattering angle Theta in the Center of Mass frame, and adjusting the weight by the number of times the specific angle caused hits.  We should recover the Moller differential cross-section as found previously.
 
 
 
 
 
Once the validity of the Moller differential cross-section is established, we can transform from the center of mass to the lab frame as shown earlier.  Since the detector is in the lab frame, the hits collected will have to be used to compose a histogram for the Moller scattering angle in the lab frame.  We can show that the Moller events that register as hits in the lab matches the Moller differential cross-section in the lab.
 
 
 
 
 
To associate the hits with the Moller scattering angle theta, the occupancy plots of the drift chamber hits by means of wire numbers and layer must be translated using the physical constraints of the detector.  Using the data released for the DC:
 
 
 
DC: Drift Chambers[https://www.jlab.org/Hall-B/clas12-web/specs/dc.pdf  (specs)]
 
 
 
 
 
This gives the detector with a working range of 5 to 40 degrees in Theta for the lab frame, with a resolution of 1m radian.
 
 
 
This sets the lower limit:
 
 
 
<center><math>\frac{5\deg}{1}\frac{\pi radians}{180\deg}=.0872664626 radians</math></center>
 
 
 
 
 
This sets the upper limit:
 
 
 
<center><math>\frac{40\deg}{1}\frac{\pi radians}{180\deg}=.698131700798\ radians</math></center>
 
 
 
Taking the difference,
 
 
 
<center><math>.698131700798-.0872664626\approx\  .61086523198\  radians</math></center>
 
 
 
 
 
Using CED to verify the angle and wire correlation,
 
 
 
[[File:Layer1Wire1Hit.png]][[File:Layer1Wire2.png]]
 

Latest revision as of 21:52, 27 July 2017

Verification using LUND and evio files

The LUND files are broken into 1000 events per file to produce manageable GEMC output file sizes. The kinematics of these Moller events is shown fin Figure 1.


Moller Momentum Center of Mass Frame
Figure 1a: A plot of Moller electron momentum in the center of mass frame.
Moller Theta Center of Mass
Figure 1b:A plot of Moller electron scattering angle theta in the center of mass frame.

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