C¹⁸O(1−0) spectra observed toward 6 filaments in Polaris. The corresponding Gaussian fits are highlighted in blue. Note 1: the spectrum observed toward filament 4 shows two velocity components. Both velocity components have similar linewidths (0.19 km s^-1 and 0.14 km s^-1, respectively), they are separated by  ~0.8 km s^-1. They most probably belong to two filaments which are seen on the same line-of-sight (but a large map would be needed to study the kinematics of the field). The component observed at  −4.5 km s^-1 has been taken to be representative of filament 4.