[C II] channel maps of the continuum-subtracted data cube of J1342+0928. The zero velocity is set to a redshift of z = 7.5413. Solid (dashed) contours outline positive (negative) values starting at 2σ with steps of 2σ, where σ is the noise in each individual channel: σ ≈ 0.07 mJy beam−1. The synthesized beam is shown in the lower left corner. The black dotted circles are the apertures (r = 1.″3) used to measure the total flux density (see Figure 2).