Evidence for an outflow in HZ4. Left panel: [C II] line integrated intensity contours with S/N ≥ 3 (yellow). The spectra extracted from the seven apertures placed across the disk are shown in Appendix B, except for apertures 1 and 2 (in purple), for which the spectra are shown in the right panels. In these cases, the best Gaussian fit to the spectra involves two components: a narrow component that we associate with the disk (green), and a broad component that we associate with outflowing gas (purple). The purple arrow in the [C II] map shows the direction in the disk were we find evidence for outflowing gas, which is almost along the galaxy minor axis (gray arrow).