Alvaro Hacar


Dense core formation by fragmentation of velocity-coherent filaments in L1517

M. Tafalla


As recently stressed by the latest Herschel results, filaments play a key role in the star formation process promoting the formation of dense cores within molecular clouds. To investigate the connection between cores and filaments we have systematically studied the L1517 region in Taurus. Our results show that the gas within this region is hihgly organized forming 4 filaments. The analysis of their internal gas kinematics shows that all these filaments are extremely quiescent showing subsonic internal motions and exhibiting a coherent velocity structure over their whole length. Moreover, two of these filaments shows large-scale velocity oscillations likely related to the core-forming flows. These results suggest that core formation ocurres in two steps. First, the subsonic, velocity-coherent filaments condense out of the more turbulent ambient cloud. Then, the cores fragmented quasi-statically and inheriting the kinematics of the filaments. (Hacar & Tafalla, 2011, arXiv:1! 107.0971)