Uniform distribution in Energy and Theta LUND files
4.1 Uniform Distribution in Energy and Theta LUND files
Due to the fact that GEMC simulations will utilize particle momentum in the lab frame, the LUND files must contain lab frame information. In the lab frame there are 3 degrees of freedom, i.e. x, y and z directions. The number of degrees of freedom can be reduced to 2 degrees of freedom in the center of mass frame of reference. The LUND file is created by creating an isotropic distribution of particles within the Moller Center of Mass frame of reference. These particles are uniformly distributed through the angle theta with respect to the beam line in the range 90-180 in the Center of Mass frame. This is done at a set angle phi (10 degrees) with respect to the perpendicular components with respect to the beam line.