Analysis of low energetic electron and pion data collected with the AHCAL prototype at Fermilab

This note presents the current status of the analysis of electron and pion data collected with the CALICE AHCAL (Analog Hadron Calorimeter) physics prototype at the Fermilab Test Beam Facility in 2008 and 2009. The experimental setup, the operation of the Čerenkov detector, the calibration of the AHCAL data, and the identification of bad cells are explained. The event selection criteria for electron and pion data and the purities of these samples are presented. Linearity and resolution of the electromagnetic response are investigated. The results are compared to the results obtained for the CERN data. Finally, the AHCAL response to negative pions and the ratio between this response and the electromagnetic response ($\frac{\pi}{e}$ ratio) are shown.