Study of the effect of solenoid field on the PANDA luminosity monitor

The conceptual design of the luminosity monitor for the PANDA experiment is based on measuring the differential elastic Antiproton-Proton scattering rate. The detector will be located at about 10 m downstream of the target and will measure forward outgoing antiprotons which are emitted at an angle of 3-8 mrad with respect to the beam axis. The angle of the scattered antiproton will be reconstructed by measuring the track with 4 planes of silicon strip detectors. The geometry of the rectangular opening of the solenoid yoke leads in an asymmetry of the x-field and y-field. As a consequence, the forward going antiprotons will be deflected relative to the beam axis. Simulation studies indicate that a small polar angle shift is correlated to a shift in the azimuthal angle and the magnitude depends upon the momentum of the emitting antiproton. This shift can be corrected based on the reconstructed trajectory and momentum of the detected antiproton using the Geane software package which was incorporated into the PANDARoot software framework. The latest results of the simulation studies will be shown in the presentation.