Query : 2003A&A...411..149K

2003A&A...411..149K - Astronomy and Astrophysics, volume 411, 149-156 (2003/11-4)

On the intrinsic shape of molecular clouds.


Abstract (from CDS):

Knowledge of the intrinsic shape of molecular clouds and molecular cloud cores provides useful information on both the formation and collapse mechanisms associated with the objects and on the initial conditions for star formation. We compare the shapes of molecular clouds as determined by the Heyer et al. (2001ApJ...551..852H, HCS01) and Brunt et al. (2003ApJS..144...47B, BKP03) catalogues of 12CO(J=1-0) emission in the outer Galaxy. The catalogues are based upon different versions of the FCRAO Outer Galaxy Survey and also utilize different techniques for defining both the extent and shape of the clouds, which allows us to examine the effects of using different cloud definition and shape-fitting algorithms. In order to compare the two catalogues we use a subset of the cloud population where the clouds are well-defined in both data sets. We model the clouds in terms of triaxial ellipsoids and use a Monte Carlo technique to determine the best-fit intrinsic shape distribution which matches the observed axis ratio distributions. Our analysis shows that the observed shapes of molecular clouds can be best described in terms of an intrinsic distribution of triaxial ellipsoids that are intermediate between near-oblate and near-prolate ellipsoids. The lack of high axis ratio clouds seen in the HCS01 catalogue is shown to be an artifact of the cloud definition algorithm and not an intrinsic property of the molecular clouds.

Abstract Copyright:

Journal keyword(s): ISM: molecules - radio lines: ISM - methods: data analysis

Simbad objects: 6

goto Full paper

goto View the references in ADS

Number of rows : 6
N Identifier Otype ICRS (J2000)
ICRS (J2000)
Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2023
1 [BKP2003] 6182 MoC 00 37 08 +64 04.2           ~ 1 0
2 [BKP2003] 6084 MoC 02 17 11 +62 02.7           ~ 1 0
3 [HCS2001] 4021 MoC 02 17.2 +62 02           ~ 1 0
4 [BKP2003] 455 MoC 22 56 49 +64 21.7           ~ 1 0
5 [BKP2003] 481 MoC 23 32 24 +59 50.7           ~ 1 0
6 [BKP2003] 9974 MoC 23 33 22 +65 28.9           ~ 1 0

To bookmark this query, right click on this link: simbad:objects in 2003A&A...411..149K and select 'bookmark this link' or equivalent in the popup menu


© Université de Strasbourg/CNRS

    • Contact