Channel maps of SO 6₅ - 5₄ (top, merged data) and SO₂ 4_2,2 - 3_1,3 (bottom, NOEMA-only data) toward L1448 IRS3C. The green color map shows the line intensity with the velocity of the channel in km s^-1 labeled in the bottom right. The black contours are the same as in Fig. 1. The dashed red and solid blue contours indicate the CO (2 - 1) integrated intensity of the red- and blueshifted outflow launched by IRS3C. The integration ranges are 5.9-27 km s^-1 and 2-3.4 km s^-1 (narrow range to avoid foreground contamination) with contour levels at 0.1, 0.3, 0.5, and 0.7 and 0.5, 0.7, and 0.9 times the peak-integrated intensity, respectively. In the top left panel, the black scale bar in the top right corner indicates a spatial scale of 1 000 au. The synthesized beam of the line and continuum data are shown in the bottom left and right corners, respectively. In each panel, the scale is set from a minimum brightness temperature of -0.3 K to a maximum of 7 K. The IRS3C source velocity is 3.8 km ^-1 (Sect. 3.3).