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Description
A mapping survey of 51 Planck cold clumps projected on the Orion complex was performed with J=1-0 lines of ^12^CO and ^13^CO with the 13.7m telescope at the Purple Mountain Observatory. The mean column densities of the Planck gas clumps range from 0.5 to 9.5x10^21^cm^-2^, with an average value of (2.9+/-1.9)x10^21^cm^-2^. The mean excitation temperatures of these clumps range from 7.4 to 21.1K, with an average value of 12.1+/-3.0K and the average three-dimensional velocity dispersion {sigma}_3D_ in these molecular clumps is 0.66+/-0.24km/s. The H2 column density of the molecular clumps calculated from molecular lines correlates with the aperture flux at 857GHz of the dust emission. By analyzing the distributions of the physical parameters, we suggest that turbulent flows can shape the clump structure and dominate their density distribution on large scales, but not function on small scales due to local fluctuations. Eighty-two dense cores are identified in the molecular clumps. The dense cores have an average radius and local thermal equilibrium (LTE) mass of 0.34+/-0.14pc and 38^+5^_-30_M_{sun}_, respectively. The structures of low column density cores are more affected by turbulence, while the structures of high column density cores are more affected by other factors, especially by gravity.
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