Supersonic Random Flows in the Perseus Molecular Cloud

نویسندگان

  • Paolo Padoan
  • Youssef Billawala
  • Mika Juvela
  • Åke Nordlund
چکیده

We compare the statistical properties of J=1→0 CO spectra observed in the Perseus Molecular Cloud with synthetic J=1→0 CO spectra from a 5 pc model cloud. The synthetic spectra are computed solving the non–LTE radiative transfer problem for a model cloud obtained as solutions of the 3–D magneto–hydrodynamic (MHD) equations in both the highly supersonic and super–Alfvénic regimes of random flows. We present several statistical results that demonstrate remarkable similarity between real data and the synthetic cloud. The three–dimensional structure and dynamics of molecular clouds like Perseus are appropriately described by random supersonic and super–Alfvénic MHD flows. Although the description of gravity and stellar radiation are essential to understand the formation of single protostars and the effects of star formation in the cloud dynamics, the overall description of the cloud and of the initial conditions for star formation can apparently be described on intermediate scales without accounting for gravity and stellar radiation. Subject headings: turbulence – ISM: kinematics and dynamics – magnetic fields – individual (Perseus Cloud); radio astronomy: interstellar: lines

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تاریخ انتشار 1997