PEP-N Simulation and Multihadron Detection

The PEP-N experiment is proposed to study e+e− collisions occurring between the LER (SLAC Low Energy Ring) positrons, which have a fixed energy of 3.12 GeV, and the electrons stored in the VLER (Very Low Energy Ring) with energy variable in the range 0.2 GeV to 0.8 GeV, which correspond to center of mass energies from about 1.5 GeV to 3.1 GeV. Because of this, the e+e− center of mass (CM) system has a boost in the e+ beam direction (forward direction). The PEP-N detector (Figure 1) has been designed to fit into a dipole vertical magnet and to have the highest possible acceptance for the reconstruction of the exclusive final states. Because of the boost of the final state particles the detector is not symmetric: the interaction point (IP) is located 25 cm upstream with respect to the center of the magnet, to take advantage of a longer path for the charged particles into the magnetic field.