Difference between revisions of "DV RunGroupC Moller"

From New IAC Wiki
Jump to navigation Jump to search
Line 20: Line 20:
  
 
E<sub>cm</sub>=[(E<sub>1</sub>+E<sub>2</sub>)<sup>2</sup>-(p<sub>1</sub>+p<sub>2</sub>)<sup>2</sup>]<sup>1/2</sup>
 
E<sub>cm</sub>=[(E<sub>1</sub>+E<sub>2</sub>)<sup>2</sup>-(p<sub>1</sub>+p<sub>2</sub>)<sup>2</sup>]<sup>1/2</sup>
E<sub>cm</sub>=[m<sub>1</sub><sup>2</sup>+m<sub>2</sub><sup>2</sup>+2E<sub>1</sub>E<sub>2</sub>(1-ß<sub>1</sub>ß<sub>2</sub>cosθ)]<sup>1/2</sup>
+
 
 +
E<sub>cm</sub>=[m<sub>1</sub><sup>2</sup>+m<sub>2</sub><sup>2</sup>+2E<sub>1</sub>E<sub>2</sub>(1-β<sub>1</sub>β<sub>2</sub>cosθ)]<sup>1/2</sup>
  
 
[[File:FinalMomCM.jpg]][[File:MollerMomCM.jpg]]
 
[[File:FinalMomCM.jpg]][[File:MollerMomCM.jpg]]

Revision as of 21:09, 23 April 2015

Simulating the Moller scattering background for EG1

Step 1

Determine the Moller background using an LH2 target to check the physics in GEANT4

Incident electron energy varies from 1-11 GeV.

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 and angular distributions. 11GeV

ElectronMomentumLabFrame.jpgMollerMomentumLabFrame.jpg

In the collision of two particles of mass m1 and m2, the total energy in the center of mass frame can be written

Ecm=[(E1+E2)2-(p1+p2)2]1/2

Ecm=[m12+m22+2E1E2(1-β1β2cosθ)]1/2

FinalMomCM.jpgMollerMomCM.jpg

FinalTheta.jpgMollerTheta.jpg

FinalThetaCM.jpgMollerThetaCM.jpg

Comparing experimental vs. theoretical for Møller differential cross section 11GeV

FinalThetaCM.jpgV3.jpg

Step 2

Replace the LH2 target with an NH3 target and compare with LH2 target.


Step 3

Determine impact of Solenoid magnet on Moller events

Papers used

A polarized target for the CLAS detectorFile: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

EG12