... cores

Based on observations with the IRAM 30 m-telescope.

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...

Figure 1, Tables 3-5 and Appendices A, B are only available in electronic form at http://www.aanda.org

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...

Data used for the maps (FITS files) is only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5), or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/487/993

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... survey

http://www.cfa.harvard.edu/gouldbelt/index.html

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... maps

Some of these data were kindly provided by A. Crapsi.

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... LABOCA

http://www.apex-telescope.org/bolometer/laboca/

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... SCUBA-2

http://www.jach.hawaii.edu/JCMT/continuum/scuba2.html

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... Bolocam

http://casa.colorado.edu/~aikinr/research/bolocam.html

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... applied)

This is implemented by using the IDL routine FitEllipse by David Fanning.

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... delivery

See
http://ssc.spitzer.caltech.edu/legacy/c2dhistory.html for a detailed documentation.

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... respectively

This analysis assumes a random distribution of the core axes in space. This might not be justified for our sample, since most of our cores are situated in a small number of star-forming regions, in which preferred orientations might prevail.

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... timescale

We give the collapse time for a homogeneous sphere of density $n({\rm H_2})$, i.e. $\tau_{\rm ff} = (3 ~ \pi [32~G ~ \varrho])^{1/2}$, where G is the constant of gravity and $\varrho$ is the volume-averaged density. Our calculation assumes a mean particle weight of 2.8 per hydrogen molecule.

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