  The PANDA detection system at FAIR, Germany, is designed to study
antiproton-proton annihilations, in order to investigate among others the realm
of charm-meson states and glueballs, which has still much to reveal. The yet
unknown properties of this field are to be unraveled through studying QCD
phenomena in the non-perturbative regime. The multipurpose PANDA detector will
be capable of tracking, calorimetry, and particle identification, and is
foreseen to run at high luminosities providing average reaction rates up to 20
Million interactions/s. The envisaged physics program requires measurements of
photons and charged particles with excellent energy, position, and time
resolutions. The electromagnetic calorimeter (EMC) will serve as one of the
basic components of the detector setup and comprises cooled Lead-Tungstate
(PbWO4) crystals. This paper presents the mechanical design of the Forward
End-cap calorimeter and analyses the response of this detector component in
conjunction with the full EMC and the complete PANDA detector. The simulation
studies are focused on the performance of the planned EMC with respect to the
energy and spatial resolution of the reconstructed photons. Results of the
Monte Carlo simulations, excluding very low-energy photons, have been validated
by data obtained from a prototype calorimeter and shown to fulfil the
requirements imposed by the PANDA physics program.
