Generalized Transport Equation for the Autocovariance Function of the Density Field and Mass Invariant in Star-forming Clouds

  title={Generalized Transport Equation for the Autocovariance Function of the Density Field and Mass Invariant in Star-forming Clouds},
  author={Etienne Jaupart and Gilles Chabrier},
  journal={The Astrophysical Journal Letters},
In this Letter, we study the evolution of the autocovariance function of density-field fluctuations in star-forming clouds and thus of the correlation length l c (ρ) of these fluctuations, which can be identified as the average size of the most correlated structures within the cloud. Generalizing the transport equation derived by Chandrasekhar for static, homogeneous turbulence, we show that the mass contained within these structures is an invariant, i.e., that the average mass contained in the… 


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