[C II]_{158 μm} (red) and dust continuum emission (blue) profiles for J1148+5251, which both extend up to ﹩\theta ={2.51}_{-0.25}^{+0.46}\ \mathrm{arcsec}﹩ at the 3σ level, corresponding to ﹩r={9.8}_{-2.1}^{+3.3}﹩ (accounting for beam convolution). The shaded areas show the corresponding 1σ noise level. A point-source profile is shown in black and the dirty (before cleaning and residual scaling) profile is shown in dashed–dotted red. The three panels show, from left to right: the radial profile integrated over the full 2π, only in the NW and SE quadrants, and finally only in the NE and SE quadrants (e.g., along the extended emission seen in Figure 3). In the latter case, the [C II]_{158 μm} emission is more extended than the FIR continuum (5.8σ significance).