J1259+0309 spectrum and MUSE narrow band images around the DLA core. Top row: J1259+0309 X-shooter 1D combined spectrum around systemic the Lyα wavelength. The solid red line shows the reconstructed quasar emission, to which the PDLA Voigt profile model (log N(H/I) ≈ 21.4) is then applied to obtain the solid purple line. Vertical dashed red and purple lines indicate the expected location of lines at the quasar systemic redshift from CO(3−2) emission (also the zero point in the velocity from the top axis) and the PDLA, respectively. The inner subpanels present a zoomed-in view in around wavelength regions containing the Lyα emission in the PDLA core and a low-ionization absorption line. Bottom row: MUSE narrowband images from the wavelength regions A and B indicated in the top panel by the vertical blue and gray stripes, respectively. The third panel shows a quasar-continuum-only region at 5400−5412 Å. All images were smoothed using a Gaussian kernel, and have the same scale, and coordinates are relative to the quasar central position in the sky. In panel A, horizontal dashed rectangles illustrate the position the two X-shooter slits employed to obtain the combined 1D spectrum. A scale of 10 proper kpc (≈1.3″) is shown as a horizontal solid black line.