(a)–(c) ﹩{\mathrm{NH}}_{3}﹩ fitted gas temperature and Mach number in comparison with SED fitted dust temperature and H2 column density (Lin et al. 2017). The contours mark ﹩{N}_{{{\rm{H}}}_{2}}={10}^{22.4},{10}^{22.5}﹩ cm−2 with major clumps labeled. (d) ﹩{\mathrm{NH}}_{3}﹩ (1, 1) PV diagram constructed from a path following the curvature of the C-shaped filament. (e) Velocity profile after subtracting the global gradient. Typical fitting uncertainty is smaller than the symbol size. (f) Lomb–Scargle periodogram of (e).