We propose that the core mass function(CMF)can be driven by filament fragmentation.To model a star-forming system of filaments and fibers,we develop a fractal and turbulent tree with a fractal dimension of 2 and a Lar...We propose that the core mass function(CMF)can be driven by filament fragmentation.To model a star-forming system of filaments and fibers,we develop a fractal and turbulent tree with a fractal dimension of 2 and a Larson's law exponent(β)of 0.5.The fragmentation driven by convergent flows along the splines of the fractal tree yields a Kroupa-IMF-like CMF that can be divided into three power-law segments with exponentsα=-0.5,-1.5,and-2,respectively.The turnover masses of the derived CMF are approximately four times those of the Kroupa IMF,corresponding to a star formation efficiency of 0.25.Adoptingβ=1/3,which leads to fractional Brownian motion along the filament,may explain a steeper CMF at the high-mass end,withα=-3.33 close to that of the Salpeter IMF.We suggest that the fibers of the tree are basic building blocks of star formation,with similar properties across different clouds,establishing a common density threshold for star formation and leading to a universal CMF.展开更多
基金support of the Strategic Priority Research Program of the Chinese Academy of Sciences under grant No.XDB0800303the National Key R&D Program of China under grant No.2022YFA1603100the National Natural Science Foundation of China(NSFC,Grant No.12203086)。
文摘We propose that the core mass function(CMF)can be driven by filament fragmentation.To model a star-forming system of filaments and fibers,we develop a fractal and turbulent tree with a fractal dimension of 2 and a Larson's law exponent(β)of 0.5.The fragmentation driven by convergent flows along the splines of the fractal tree yields a Kroupa-IMF-like CMF that can be divided into three power-law segments with exponentsα=-0.5,-1.5,and-2,respectively.The turnover masses of the derived CMF are approximately four times those of the Kroupa IMF,corresponding to a star formation efficiency of 0.25.Adoptingβ=1/3,which leads to fractional Brownian motion along the filament,may explain a steeper CMF at the high-mass end,withα=-3.33 close to that of the Salpeter IMF.We suggest that the fibers of the tree are basic building blocks of star formation,with similar properties across different clouds,establishing a common density threshold for star formation and leading to a universal CMF.
