Difference between revisions of "DV RunGroupC Moller"

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  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.
 
  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.
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Scanning from 2MeV to 5500MeV, and 0 to 36 degrees in Theta.
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For Solenoid on with 5T:
  
 
<pre>
 
<pre>

Revision as of 16:27, 21 April 2016

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

Simulating the Moller scattering background for EG12

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>

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

Calculations of 4-momentum components

Alter Phi Angles

Check Differential Cross-Section

Running Expanded LUND files in GEMC


Back to Recon

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



EG12