J/A+A/357/1020 JHK photometry in NGC 6334 IV (Persi+, 2000)
The NGC 6334 IV massive star formation site: A cluster in the making?
Persi P., Tapia M., Roth M.
<Astron. Astrophys. 357, 1020 (2000)>
=2000A&A...357.1020P 2000A&A...357.1020P
ADC_Keywords: Photometry, infrared ; Nebulae
Keywords: stars: formation - ISM: clouds - ISM: dust, extinction -
ISM: HII regions - infrared: stars
Abstract:
Sub-arcsecond JHK images of the star formation region NGC 6334 IV
covering 14.7arcmin2 have been obtained. These were supplemented by
H2 and Brγ images of the central 2arcmin2. A total of
1238sources brighter than K≃17 were detected. Due to the very high
extinction in this region, only 685 of these are brighter at 1.2µm
than our limit, J≃20. Only less than 5% of the sources exhibit excess
emission at λ>2.0µm and they are scattered over the whole
area covered. No evidence of a developed stellar cluster was found,
but a small number of luminous (O-B2) young stellar objects were
detected. These are embedded in the densest part of the molecular
cloud that is at the centre of a giant bipolar structure seen in the
radio and the infrared. This morphology is the result of the effect of
massive stellar winds originating from the centre of a dense molecular
toroid which collimates the outflow material giving rise to two lobes
of thermal gas and dust emission. We confirm that the extinction is
higher toward the southern lobe than toward the northern one but both
are less reddened than their immediate surroundings. A new centre of
active massive star formation is reported to the east of the central
region. Close to a (sub)millimeter emission peak, a large infrared
nebula with several point-like sources was found at 2.2µm. The
discovery of a small embedded low-luminosity bipolar object in the
vicinity of one of the giant lobes is also reported.
For a description of the JHK photometric system, see e.g. GCPD/09
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 58 1238 Coordinates and photometry of sources
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See also:
J/A+A/316/102 : JHK Photometry in NGC 6334 (Tapia+, 1996)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 2 I2 h RAh Right Ascension (B1950)
4- 5 I2 min RAm Right Ascension (B1950)
7- 12 F6.3 s RAs Right Ascension (B1950)
14 A1 --- DE- Declination sign (B1950)
15- 16 I2 deg DEd Declination (B1950)
18- 19 I2 arcmin DEm Declination (B1950)
21- 25 F5.2 arcsec DEs Declination (B1950)
27- 31 F5.2 mag Kmag K magnitude
33- 36 F4.2 mag e_Kmag rms uncertainty on Kmag
38- 42 F5.2 mag Hmag ? H magnitude
44- 47 F4.2 mag e_Hmag ? rms uncertainty on Hmag
49- 53 F5.2 mag Jmag ? J magnitude
55- 58 F4.2 mag e_Jmag ? rms uncertainty on Jmag
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Acknowledgements: Paolo Persi
(End) Patricia Bauer CDS 24-Mar-2000