J/AJ/106/220 UBVI photometry in Berkeley 31 (Guetter 1993)
Photometric study of the old galactic cluster Be 31
GUETTER H.H.
<Astron. J. 106, 220 (1993)>
=1993AJ....106..220G 1993AJ....106..220G
ADC_Keywords: Clusters, open; Photometry, CCD; Photometry, UBV
Abstract:
CCD photometry on the Johnson UBV and on the Kron-Cousins VI systems
are presented for 732 stars in and near Be 31, an open cluster located
towards the galactic anticenter. The resultant color-magnitude
diagrams indicate that the cluster is an old object. From the
color-color diagram, the reddening and metallicity parameters are
determined to be E(B-V) = 0.13 mag and [Fe/H] = -0.4. By comparing the
cluster C-M diagrams with the VandenBerg isochrones, and by assuming a
normal reddening law, a distance of 5.2 ± 0.5 kpc and an age of 8 Gyr
are derived.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1 42 732 Observational data
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Byte-by-byte Description of file: table1
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Bytes Format Units Label Explanations
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1- 3 I3 --- No Star number
4- 10 F7.2 mag Vmag V magnitude
11- 16 F6.2 mag B-V []? B-V color
17- 22 F6.2 mag U-B []? U-B color
23- 28 F6.2 mag V-I []? V-I color
29- 35 F7.1 pix X X coordinate
36- 42 F7.1 pix Y Y coordinate
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Note:
This table contains 732 records and has a maximum record length of 42 bytes.
Be 31 (OCl 513, 1950 RA = 06 54.9, Dec = +08 20, l = 206.3 deg, b = 5.1 deg)
is an open cluster located toward the direction of the galactic anticenter.
The detector was a TI 800x800 thinned CCD which was UV flooded. The detector-
telescope combination provides a field of view of 5.7x5.7 arcmin, which
corresponds to a pixel size of 0.43 arcsec. In the pixel coordinates described
above, the top left or northeast corner is (1,1) and the bottom right is
(800,800).
The instrumental magnitudes and colors were transformed linearly to the
Johnson and Kron-Cousins system by using measures of 16 Landolt standards
(1983) in seven fields. The mean errors in converting the instrumental
magnitude system to the standard systems were 0.012, 0.019, 0.012 and
0.012 mag for (V-I), V, (B-V), and (U-B), respectively.
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Origin: AAS CD-ROM series, Volume 1, 1993
(End) Patricia Bauer [CDS] 22-Jun-1994