Particle Background simulation for a triple Germanium Cluster detectors at PANDA

For the high resolution spectroscopy of excited hypernuclear states a position sensitive Germanium γ–array [1] [2] has been implemented in the standard PANDA framework PANDAroot. In the simulation encapsulated n–type Germanium crystals are arranged asymmetrically to form a triple cluster [3]. The total γ–array set-up consists of 15 triple Germanium cluster detectors positioned at backward axial angle around the target region. [4] Hereby the main limitation is the load of high particles rate from background reactions. The influence of this particle background has been simulated to investigate the feasibility of operating this kind of detectors under these condictions. Background reactions have been calculated by using the UrQMD+Smm [5] event Generator to produce 10000 p + C interactions at 3 GeV/c (see fig. 1). Most of the produced charged and neutrals particles are emitted into the forward region not covered by the Germanium array. Those charged particles emitted into backward axial angles are very low in kinetic energy, and will be absorved in a large fraction in the material surrounding the target. More critical are nevertheless neutrons emitted into the backward direction which can contribute to the radiation damage of the detector. Fig. 2 shows the kinetic energy distribution of protons and neutrons entering the surface of the Germanium detec-