Two-color image toward Reg. 1b with the radio continuum emission at 20 cm (from MAGPIS) displayed in blue and the ATLASGAL emission at 870 μm in green. The color ranges are the same as in Fig. 2. For context, the box of Reg. 1 and the 56, and 68 K km s^-1 contours (in dashed yellow line) of the ¹²CO emission presented in Fig. 2 are also shown. Contours of the ¹³CO J = 3−2 emission integrated between 15 and 26 km s^-1 are shown in white, with levels of 12.0, 15.0, 16.5, and 20.0 K km s^-1. The beam of the molecular observations is shown in the top right corner.