map making were done using the software PACSman [@lebouteiller-2012]. The signal from each spatial position of the PACS array is fitted with a second order polynomial plus Gaussian for the baseline and line. For total uncertainties, we add 30% of the line flux due to calibration uncertainties [@poglitsch-2010]. The rasters are combined by drizzling to produce final reduced maps with pixel size of 3$^{\prime\prime}$.

With [*Herschel*]{}, all of the lines are well detected, at least in the central pixel of the PACS array, except the \[N [ii]{}\] 205 $\mu$m line. The \[N [ii]{}\] 205 $\mu$m line is located at the edge of the first grating order of the spectrometer and affected by spectral leakage, due to overlapping of the grating orders. It is contaminated by signal from the second grating order around 100 $\mu$m, and is therefore difficult to observe and to calibrate. The line profiles are displayed in Figure \[fig:pacs\_lines\]. The line centers range between -30 and +70 km s$^{-1}$ within the maps of all observed lines, and indicate a rotation around the north-south axis of both the ionised and neutral gas components, slightly tilted compared to the velocity structure of H${\rm{\alpha}}$ analysed in [@ostlin-1999]. All lines display broad 