We present the results of molecular lines and polarized dust continuum mapping observations toward the prestellar core, L1544, using JCMT/HARP and JCMT/SCUBA2/POL2, respectively, to investigate the role of the filamentary structures in the dense core formation and the initial condition of the low-mass star formation. We found the 0.5 pc-long velocity-coherent filamentary clouds around the L1544 core and examined its velocity structure by Gaussian fit for the C18O (3?2) and 13CO (3?2) spectra. The results show that both core and filament have a nonthermal velocity dispersion smaller than or comparable to the thermal sound speed. We also identified the periodic velocity oscillation along the filament's skeleton (main axis) and its phase shift of 1/4 wavelength from the column density variation. From the velocity gradient around the core, the mass accretion rate was estimated to be a few solar masses per million years. In addition, we found the dominant blue profiles in the core region from 13CO (3?2) and HCO+ (4?3) spectra, which trace the outer and innermost areas of dense cores, respectively. Lastly, we found the plane-of-sky magnetic field directions are fairly parallel to the long axis in the outer area of the core, while that is distributed in the radial direction around the peak position of the core, implying the hourglass-shaped magnetic field morphology. From these results, we suggest that the velocity-coherent filaments could be formed from the shock compression by colliding turbulent flows, and then the cores are formed and evolved by gravity-dominated processes, such as filament fragmentation, axial-accretion along the filament, and core collapsing. We also suggest that, in this process, the magnetic fields might be dragged and distorted by the gas flow motions.
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