Efficiency calculation for π^- + C and π^- + H₂ reactions at HADES

The study of strangeness production in hadronic matter is a major topic in the field of experimental nuclear physics, which requires modern and capable detector systems like the HADES detector. At SIS 18 at GSI Darmstadt this spectrometer provides excellent conditions to study rare states of matter like Φ, K^-, K⁺, anti ω, anti K⁰_s in a precise way. For the reconstruction of these states the detection efficiencies of all sub-detectors of the HADES setup has to be determined in an precise way. To do so, an correction procedure based on full physical quantities for the HADES detector was developed, using a secondary π^- beam in the momentum region of 690 MeV/c impinging on a Carbon and Polyethylene (C₂H₄) target. Explicitly the kinematic characteristics of elastic scattering of this system was used to obtain a correction map in Φ, Θ and momentum, which allows to extract corrected cross sections and yields of the studied reactions in the target. In this poster the detailed procedure as well as the results are illustrated.