Left: acquisition image of the nuclear region of NGC 1097 from the SOAR observation of MJD56194. The cyan dashed line represents the slit (width of 103). The blue square (A) shows the extraction window (103 × 10) of the nuclear spectrum. The green squares (B and C), centered at 20 from the nucleus show the windows used to extract stellar population spectra. Right: (a) top: nuclear spectrum extracted from window A; (b) middle: mean spectrum of B and C, adopted as representative of the nuclear stellar population; (c) bottom: difference between (a) and (b) (after scaling), which isolates the nuclear emission.