Connecting the Dots: Analyzing Synthetic Observations of Star-Forming Clumps in Molecular Clouds

Abstract

In this paper, we investigate the extent to which observations of molecular clouds can correctly identify and measure star-forming clumps. We produced a synthetic column density map and a synthetic spectral-line data cube from the simulated collapse of a 5000 M${}_{\odot }$ molecular cloud. By correlating the clumps found in the simulation to those found in the synthetic observations, clump masses derived from spectral-line data cubes were found to be quite close to the true physical properties of the clumps. We also find that the `observed' clump mass function derived from the column density map is shifted by a factor of ~ 3 higher than the true clump mass function, due to projection of low-density material along the line of sight. Alves et al. (2007) first proposed that a shift of a clump mass function to higher masses by a factor of 3 can be attributed to a star formation efficiency of 30 %. Our results indicate that this finding may instead be due to an overestimate of clump masses determined from column density observations.

8 pages, 7 figures, Accepted for publication in the Astrophysical Journal

References in corpus (12)

• Cold Dark Clouds: The Initial Conditions for Star Formation
• SPLASH: An interactive visualisation tool for Smoothed Particle Hydrodynamics simulations
• Structural Analysis of Molecular Clouds: Dendrograms
• Modeling Collapse and Accretion in Turbulent Gas Clouds: Implementation and Comparison of Sink Particles in AMR and SPH
• The Mass Distribution and Lifetime of Prestellar Cores in Perseus, Serpens, and Ophiuchus
• The Effects of Radiative Transfer on Low-Mass Star Formation
• The Large and Small Scale Structures of Dust in the Star-Forming Perseus Molecular Cloud
• The Perils of Clumpfind: The Mass Spectrum of Sub-structures in Molecular Clouds
• The structure of molecular clouds and the universality of the clump mass function
• On the Evolution of the Dense Core Mass Function
• On the fidelity of the core mass functions derived from dust column density data
• Mass distributions of stars and cores in young groups and clusters

Cited by in corpus (1)

• Evolving Molecular Cloud Structure and the Column Density Probability Distribution Function