J/MNRAS/299/834 Berkeley 21 BVI photometry (Tosi+, 1998)
Old open clusters : the interesting case of Berkeley 21.
Tosi M., Pulone L., Marconi G., Bragaglia A.
<Mon. Not. R. Astron. Soc. 299, 834 (1998)>
=1998MNRAS.299..834T 1998MNRAS.299..834T
ADC_Keywords: Clusters, open ; Photometry, CCD ; Photometry, UBVRI
Keywords: Hertzsprung-Russell (HR) diagram -
open clusters and associations: general -
open clusters and associations: individual: Berkeley 21
Abstract:
We present CCD BVI photometry of the old open cluster
Berkeley 21, one of the most distant clusters in the Galactic
anticentre direction, and possibly the lowest metallicity
object in the open clusters sample. Its position and metal abundance
make it very important for the study of the Galactic disc. Using the
synthetic colour-magnitude diagram method, we estimate values for the
distance modulus (m-M)0=13.4-13.6, reddening E(B-V)=0.74-0.78 (with
possible differential absorption), and age= 2.2-2.5Gyr.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table.dat 65 1567 Photometry BVIc and positions for 1567 stars
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Byte-by-byte Description of file: table.dat
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Bytes Format Units Label Explanations
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1- 4 I4 --- TPM Identification number
(Cl* Berkeley 21 TPM NNNN in Simbad)
6- 11 F6.3 mag Vmag V magnitude (1)
13- 17 F5.3 mag V-Ic Cousins V-I colour index
19- 23 F5.3 mag B-V ? B-V colour index
26- 32 F7.2 pix Xpix X position (1pix=0.377")
35- 41 F7.2 pix Ypix Y position (1pix=0.377")
44 I1 h RAh Right ascension (J2000)
46- 47 I2 min RAm Right ascension (J2000)
49- 50 I2 s RAs Right ascension (J2000)
51 A1 --- DE- Declination sign (J2000)
52- 53 I2 deg DEd Declination (J2000)
55- 56 I2 arcmin DEm Declination (J2000)
58- 59 I2 arcsec DEs Declination (J2000)
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Note (1): V magnitude derived from calibration of B-V for stars 1-1138,
derived from V-Ic calibration for stars 1139-1567
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Acknowledgements: Angela Bragaglia
(End) Patricia Bauer [CDS] 24-Jan-2000