J/A+A/582/A66 SABOCA NGC 3603 IRS 9A images (Hummel+, 2015)
Massive envelopes and filaments in the NGC 3603 star forming region.
Hummel C.A., Stanke T., Galvan-Madrid R., Koribalski B.S.
<Astron. Astrophys. 582, A66 (2015)>
=2015A&A...582A..66H 2015A&A...582A..66H (SIMBAD/NED BibCode)
ADC_Keywords: H II regions ; Infrared sources ; Millimetric/submm sources
Keywords: circumstellar matter - stars: early-type - stars: formation -
stars: pre-main sequence - stars: individual: NGC3603
Abstract:
The formation of massive stars and their arrival on the zero-age
main-sequence occurs hidden behind dense clouds of gas and dust. In
the giant HII region NGC 3603, the radiation of a young cluster of OB
stars has dispersed dust and gas in its vicinity. At a projected
distance of 2.5pc from the cluster, a bright mid-infrared (mid-IR)
source (IRS 9A) was identified as a massive young stellar object
(MYSO), located on the side of a molecular clump (MM2) of gas facing
the cluster. We investigated the physical conditions in MM2, based on
APEX sub-mm observations using the SABOCA and SHFI instruments, and
archival ATCA 3mm continuum and CS spectral line data. We resolved MM2
into several compact cores, one of them closely associated with
IRS 9A. These are likely to be infrared dark clouds because they do
not show the typical hot-core emission lines and are mostly opaque
against the mid-IR background. The compact cores have masses of up to
several hundred times the solar mass and gas temperatures of about
50K, without evidence of internal ionizing sources. We speculate that
IRS 9A is younger than the cluster stars, but is in an evolutionary
state after the compact cores.
Description:
Observations of NGC 3603 MM2 at 350um with the SABOCA bolometer array
attached to the APEX telescope on the Chajnantor plateau in Chile were
carried out on September 15, 2011, providing a beam FWHM of 7.8". The
precipitable water vapor column was about 0.2mm during the
observations, which lasted about 15 minutes for a spiral raster map of
about 1.5 arcminutes in radius centered on IRS 9A.
Objects:
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RA (2000) DE Designation(s)
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11 15 11.87 -61 17 00.6 NGC 3603 MM2 = [NBY2002] MM 2
11 15 11.34 -61 16 45.2 NGC 3603 IRS 9A = [FPA77] NGC 3603 IRS 9A
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
list.dat 63 1 Information on fits file
IRS9A_10.fits 2880 75 SABOCA fits images
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See also:
J/ApJ/799/100 : Herschel FIR observations of NGC3603 (Cecco+, 2015)
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 (J2000)
10- 18 F9.5 deg DEdeg Declination (J2000)
20- 23 F4.2 arcsec/pix Scale Scale of the image
25- 27 I3 --- Nx Number of pixels along X-axis
29- 31 I3 --- Ny Number of pixels along Y-axis
34- 35 I2 Kibyte size Size of FITS file
37- 49 A13 --- FileName Name of the fits file
51- 63 A13 --- Title Title of the file
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Acknowledgements:
Christian Hummel, chummel(at)eso.org
(End) Patricia Vannier [CDS] 06-Oct-2015