The Bluer half of the MUSE spectrum of the nuclear source is shown in gray. The signal is integrated from all the spaxels enclosed within the red circle, as shown in the inset image. The vertical red dashed lines mark four emission lines used to characterize the ionization type through a [NII] BPT diagram, which is also shown in the inset. We showed three diagnostic lines from Kauffmann et al. (2003) (solid), Kewley et al. (2001) (dashed), and Schawinski et al. (2007) (dotted) in the BPT diagram for characterizing our measurements. The vertical green shaded lines represent regions of known optical sky lines. Two prominent absorption lines, Mg b 5176 Å and Na I D 5895 Å, are marked by blue dashed lines.