J/MNRAS/353/1025 JHK photometry of 4 W51 star clusters (Nanda+, 2004)
Embedded star clusters in the W51 giant molecular cloud.
Nanda Kumar M.S., Kamath U.S., Davis C.J.
<Mon. Not. R. Astron. Soc., 353, 1025-1034 (2004)>
=2004MNRAS.353.1025N 2004MNRAS.353.1025N
ADC_Keywords: H II regions ; Molecular clouds ; Photometry, infrared
Keywords: turbulence - stars: formation - ISM: clouds - H II regions -
ISM: individual: W51 GMC - infrared: stars
Abstract:
We present sub-arcsecond (0.35-0.9"), near-infrared J-, H- and K-band
photometric observations of six fields along the W51 giant molecular
cloud (W51 GMC). Our observations reveal four new, embedded clusters
and provide a new high-resolution (0.35") view of the W51 IRS2
(G49.5-0.4) region. The cluster associated with G48.9-0.3 is found to
be a double cluster enclosed in a nest of near-infrared nebulosity. We
construct stellar surface density maps for four major clusters in the
W51 GMC. These unveil the underlying hierarchical structure.
Description:
NIR observations were made at the 3.8-m United Kingdom Infrared
Telescope (UKIRT) with the facility imager UFTI. The UFTI pixel scale
measures 0.091"; the available field of view is ∼90". Photometric
observations through JHK broad-band filters were secured for six
fields during three nights of service observing (2000 September 15,
2001 May 31 and 2001 August 12).
Fields:
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RA (2000) DE Designation(s)
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19 22 14 +14 03 09 G48.9-0.3
19 22 26 +14 06 46 G49.0-0.3
19 23 02 +14 16 41 G49.2-0.3
19 23 40 +14 31 07 G49.5-0.4
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 70 502 Photometry for sources in the field G48.9-0.3
table3.dat 70 566 Photometry for sources in the field G49.0-0.3
table4.dat 70 272 Photometry for sources in the field G49.2-0.3
table5.dat 70 399 Photometry for sources in the field G49.5-0.4
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Byte-by-byte Description of file: table2.dat table3.dat table4.dat table5.dat
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Bytes Format Units Label Explanations
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1- 2 I2 h RAh Right ascension (J2000)
4- 5 I2 min RAm Right ascension (J2000)
7- 12 F6.3 s RAs Right ascension (J2000)
14 A1 --- DE- Declination sign (J2000)
15- 16 I2 deg DEd Declination (J2000)
18- 19 I2 arcmin DEm Declination (J2000)
21- 25 F5.2 arcsec DEs Declination (J2000)
28- 33 F6.3 mag Kmag K magnitude
36- 40 F5.3 mag e_Kmag rms uncertainty on Kmag
43- 48 F6.3 mag Hmag H magnitude
51- 55 F5.3 mag e_Hmag rms uncertainty on Hmag
58- 63 F6.3 mag Jmag J magnitude
66- 70 F5.3 mag e_Jmag rms uncertainty on Jmag
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 21-Mar-2005