Channel maps of H₂CO 3₁₂ − 2₁₁ towards DG Tau. The blue and red contours show the emission at symmetric blue- and redshifted velocities with respect to systemic (V_sys = +6.24 km s⁻¹), as labeled in the upper right corner (V − V_sys in km s⁻¹). The first contour is at 5σ with steps of 3σ. The black star and contour indicates the peak and the 5σ level of the 1.3 mm continuum. The ellipse in the bottom right corner of the last channel map shows the ALMA synthesized beam.