J/A+A/575/A79 SPIRE 250um maps of 4 molecular clouds (Schneider+, 2015)
Understanding star formation in molecular clouds.
I. Effects of line-of-sight contamination on the column density structure.
Schneider N., Ossenkopf V., Csengeri T., Klessen R., Federrath C.,
Tremblin P., Girichidis P., Bontemps S., Andre P.
<Astron. Astrophys. 575, A79 (2015)>
=2015A&A...575A..79S 2015A&A...575A..79S
ADC_Keywords: Molecular clouds ; Millimetric/submm sources
Keywords: dust, extinction - ISM: clouds - ISM: submillimeter -
methods: data analysis - ISM: general
Abstract:
Column-density maps of molecular clouds are one of the most important
observables in the context of molecular cloud- and starformation (SF)
studies. With the Herschel satellite it is now possible to precisely
determine the column density from dust emission, which is the best
tracer of the bulk of material in molecular clouds. However,
line-of-sight (LOS) contamination from fore- or background clouds can
lead to overestimating the dust emission of molecular clouds, in
particular for distant clouds. This implies values that are too high
for column density and mass, which can potentially lead to an
incorrect physical interpretation of the column density probability
distribution function (PDF). In this paper, we use observations and
simulations to demonstrate how LOS contamination affects the PDF. We
apply a first-order approximation (removing a constant level) to the
molecular clouds of Auriga and Maddalena (low-mass star-forming), and
Carina and NGC3603 (both high-mass SF regions).
Description:
SPIRE 250um map in units [MJy/sr].
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
list.dat 139 4 List of FITS images
fits/* . 4 Individual FITS images
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Byte-by-byte Description of file: list.dat
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Bytes Format Units Label Explanations
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1- 9 F9.5 deg RAdeg Right Ascension of center (J2000)
10- 18 F9.5 deg DEdeg Declination of center (J2000)
20 I1 arcsec/pix Scale [6] Scale of the image
22- 25 I4 --- Nx [779/4015] Number of pixels along X-axis
27- 30 I4 --- Ny [594/4166] Number of pixels along Y-axis
32- 37 I6 Kibyte size [1817/130688] Size of FITS file
39- 65 A27 --- FileName Name of FITS file, in subdirectory fits
67-139 A73 --- Title Title of the file
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Acknowledgements:
Nicola Schneider, nschneid(at)cea.fr
(End) Patricia Vannier [CDS] 28-Jan-2015