DV Creating LUND Files: Difference between revisions
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==8:W== | ==8:W== | ||
The invariant mass of the final hadronic system | |||
<math>W^2=(p+q)^2=M^2+2M\nu+q^2=M^2+2M\nu-Q^2</math> | |||
==9:<math>Q^2</math>== | ==9:<math>Q^2</math>== | ||
Revision as of 18:36, 29 March 2016
The LUND format
| Column | Quantity |
|---|---|
Where
1:Number of Particles
This line tells how many particles follow the header line. For Moller Scattering, this number should always be 2.
2:Number of Target Nucleons
For this simulation, only an electron-electron collision is considered. This quantity is always set to 1 for the one stationary electron we consider the incident electron scattering from.
3:Number of Target Protons
For Moller Scattering, there are no target protons. This number is set to 1, but does not have any effect within the GEMC simulations.
4:Target Polarization
This represents the polarization of the target material, either positive or negative 1. This value is always set to 1 and has no effect within the GEMC simulations.
5:Beam Polarization
This represents the polarization of the electron beam, either negative or positive 1. This value is always set to positive 1.
6:x
This represents the Bjorken x scaling variable.
[math]\displaystyle{ x=\frac{-q^2}{2p\cdot q}=\frac{-q^2}{2M\nu} }[/math]
Where M is the rest mass-energy of the proton[math]\displaystyle{ M\approx 938MeV }[/math]
7:y
[math]\displaystyle{ y=\frac{p\cdot q}{p\cdot k}=\frac{\nu}{E} }[/math]
8:W
The invariant mass of the final hadronic system
[math]\displaystyle{ W^2=(p+q)^2=M^2+2M\nu+q^2=M^2+2M\nu-Q^2 }[/math]
9:[math]\displaystyle{ Q^2 }[/math]
This represents the squared 4-momentum-transfer vector q of the exchanged virtual photon.
[math]\displaystyle{ Q^2\equiv -q^2 }[/math]
Where q is the momentum transfer betwwn the incident electron and target via the virtual photon.
[math]\displaystyle{ q\equiv k_i-k_f }[/math]
10:[math]\displaystyle{ \nu }[/math]
This represents the energy loss between scattering electrons.
[math]\displaystyle{ \nu = \frac{p\cdot q}{M} }[/math]
This can be written in the Lab frame as:
[math]\displaystyle{ \nu\equiv E-E' }[/math]
where E and E' are the initial and final electron energies.