Zeroth and first moment maps of field 7 (bottom) and field 8 (top). For the calculation of zeroth and first moment maps, please consult the text in Sect. 4. Field 7 was integrated from  −18 km s^-1 to  +25 km s^-1 and field 8 from  −15 km s^-1 to  +22 km s^-1. In the images only those pixels are displayed that have a signal above 3σ in at least 3 velocity channels. The zeroth and first moment maps are displayed in units of K km s^-1 and km s^-1, respectively.