FRACTAL DIMENSIONS OF INTERSTELLAR MEDIUM: I. THE MOLECULAR CLOUDS IN THE ANTIGALACTIC CENTER

다국어 초록 (Multilingual Abstract)

We have estimated the fractal dimension of the molecular clouds in the Antigalactic Center based onthe12CO (J = 1 - 0) and13CO (J = 1- 0) database obtained using the 14m telescope at Taeduk RadioAstronomy Observatory. Using a developed code within IRAF, we were able to identify slice-clouds,and determined the dispersions of two spatial coordinates as well as perimeters and areas. The fractaldimension of the target region was estimated to beD = 1 :34 for low resolution12CO (J = 1- 0)database, and D = 1.4 for higher resolution12CO (J = 1- 0) and13CO (J = 1 0) database, whereP ∝ A^D/ 2. The sampling rate (spatial resolution) of observed data must be an important parameterwhen estimating fractal dimension. Our database with higher resolution of 1 arcminute, which iscorresponding to 0.2 pc at a distance of 1.1 kpc, gives us the same estimate of fractal dimensionto that of local dark clouds. Fractal dimension is apparently invariant when varying the thresholdtemperatures applied to cloud identication. According to the dispersion pattern of longitudes andlatitudes of identied slice-clouds, there is no preference of elongation direction.

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