We observed NH3 emission on an extended map in TMC-1, a filamentary cloud in Taurus. With high S/N and high
velocity resolution it was possible to derive the velocity distribution of multiple line components in the
cloud and to calculate gas parameters on several positions. Herschel SPIRE observations were also used to
calculate the physical parameters in the region, then the continuum-based and gas emission-based values were
compared. We used the k-means clustering method in the position-velocity-column density parameter space for
the first time to investigate the substructures of TMC-1. We separated four sub-filaments in TMC-1 that are
close to gravitational equilibrium and have very low turbulent velocity dispersion. Three of them are very
elongated, dense and cold. The fourth, TMC-1F3 is somewhat warmer, positioned around 0.1 pc behind the main
ridge of TMC-1 and probably heated by IRAS 04381+2540 that is embedded in it. The recently proposed "fray
and fragment" filament evolution scenario was examined as a possible mechanism for the evolution of TMC-1.
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