J/A+A/360/529 BVI photometry of 4 young open clusters (Piatti+, 2000)
Photometric and integrated spectral study of the young open clusters Pismis 22,
NGC 6178, NGC 6216 and Ruprecht 130
Piatti A.E., Claria J.J., Bica E.
<Astron. Astrophys. 360, 529 (2000)>
=2000A&A...360..529P 2000A&A...360..529P
ADC_Keywords: Clusters, open ; Photometry, CCD ; Photometry, UBVRI
Keywords: Galaxy: open clusters and associations: general -
Galaxy: open clusters and associations: individual:
Pismis 22, NGC 6178, NGC 6216, Ruprecht 130
Abstract:
We present CCD observations in the B, V, and I passbands obtained for
stars in the fields of the open clusters Pismis 22, NGC 6178, NGC
6216, and Ruprecht 130, projected not far from the Galactic centre
(|l|<30°, |b|<2°). The sample consists of about 790 stars
reaching down to V∼18-19mag. From the analysis of the colour magnitude
diagrams, we confirmed the physical reality of the clusters and
derived their reddening, distance and age. In addition, we obtained
flux-calibrated integrated spectra in the range 3500-9200Å for the
cluster sample. The equivalent widths of the Balmer lines provided us
with age estimates, while the comparison with template spectra allowed
us to derive both foreground reddening and age. The photometric and
spectroscopic results reveal that the four studied objects are young
open clusters with ages ranging between 35 and 50Myr. The clusters,
located between 1.0kpc and 4.3kpc from the Sun, are affected by
different amounts of interstellar visual absorption (0.6≃Av≃6.0).
Objects:
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RA (2000) DE Designation(s)
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16 14 09 -51 52.0 Pismis 22
16 35 42 -45 38.0 NGC 6178
16 49 24 -44 44.0 NGC 6216
17 47 36 -30 07.0 Ruprecht 130
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 64 187 Pismis 22 field magnitudes and colours of stars
table4.dat 64 57 NGC 6178 field magnitudes and colours of stars
table5.dat 64 199 NGC 6216 field magnitudes and colours of stars
table6a.dat 64 212 Ruprecht 130 BVI magnitudes and colours of stars
table6b.dat 51 345 Ruprecht 130 VI magnitudes and colours of stars
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See also:
J/A+A/370/931 : Melotte 105, Hogg 15, Pismis 21, Ruprecht 140 (Piatti+, 2001)
Byte-by-byte Description of files: table[345].dat table6a.dat
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Bytes Format Units Label Explanations
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1- 4 A4 --- Seq Running number
6- 12 F7.3 pix Xpos X coordinate (1)
14- 20 F7.3 pix Ypos Y coordinate (1)
22- 27 F6.3 mag Vmag V magnitude
29- 33 F5.3 mag e_Vmag V error
35- 40 F6.3 mag B-V B-V colour index
42- 46 F5.3 mag e_B-V B-V error
48- 53 F6.3 mag V-I V-I colour index
55- 59 F5.3 mag e_V-I V-I colour index
64 I1 --- o_Vmag Number of measurements
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Note (1): North is up and East is to the left. 1 pix = 0.45".
See Fig.1 for adopted cluster center.
They are approximatively:
Pismis 22: X=190, Y=160; NGC 6178: X=300, Y=280
NGC 6216: X=280, Y=240; Ruprecht 130: X=190, Y=300
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Byte-by-byte Description of file: table6b.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 A4 --- Seq Running number
6- 12 F7.3 pix Xpos X coordinate (1)
14- 20 F7.3 pix Ypos Y coordinate (1)
22- 27 F6.3 mag Vmag V magnitude
29- 33 F5.3 mag e_Vmag V error
35- 40 F6.3 mag V-I V-I colour
42- 46 F5.3 mag e_V-I V-I error
51 I1 --- o_Vmag Number of measurements
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Note (1): North is up and East is to the left. 1 pix = 0.45".
See Fig.1 for adopted cluster center.
It is approximatively:
Ruprecht 130: X=190, Y=300
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Acknowledgements: Andres Piatti
(End) Patricia Bauer [CDS] 28-Aug-2000