Response matrix file (RMF) of the eROSITA telescope for telescope module TM1. Left: Full-resolution RMF in the 0.2 keV to 4.5 keV range, showing the probability distribution of detected energies (horizontal axis) for incident photon energies (vertical axis). The dashed white line marks the ideal one-to-one relation E_true = E_det. Right: The same response integrated into three broad bands (0.2 keV to 1.0 keV, 1.0 keV to 2.0 keV, and 2.0 keV to 4.5 keV), yielding a 3 × 3 representation of the energy redistribution. Cell values indicate normalized detection probabilities, and grid lines mark the bin boundaries. The nearly diagonal structure demonstrates that spectral bleeding is negligible for the purposes of this work.