J/A+A/429/607 BV photometry of Berkeley 36, 73 and 34 (Ortolani+, 2005)
The old open clusters Berkeley 36, Berkeley 73 and Biurakan 13 (Berkeley 34).
Ortolani S., Bica E., Barbuy B., Zoccali M.
<Astron. Astrophys. 429, 607 (2005)>
=2005A&A...429..607O 2005A&A...429..607O
ADC_Keywords: Clusters, open ; Photometry, UBV
Keywords: Galaxy: open clusters and associations: individual: Berkeley 36,
Berkeley 73, Biurakan 13 - stars: Hertzsprung-Russell (HR) and C-M
Abstract:
BV photometry of the faint open clusters Berkeley 36, Berkeley 73 and
Biurakan 13 are studied. For these clusters no colour-magnitude
analyses were previously available. The colour-magnitude Diagrams
indicate that they are all old open clusters. The derived ages are
∼4Gyr for Berkeley 36, and ∼2.3Gyr for both Berkeley 73 and Biurakan 13.
The clusters are not very reddened, with E(B-V)=0.25, 0.10 and 0.30
respectively for Berkeley 36, Berkeley 73 and Biurakan 13. Berkeley 36
and Berkeley 73 are located at a distance from the Galactic center of
10kpc, while Biurakan 13 is much farther, at 15kpc. A peak in the age
distribution appears at 5Gyr suggesting a distinct star forming event
in the disk.
Description:
The observations were carried out on 2000, February 2-5, using the
3.5m Galileo National Telescope operating at La Palma. The instrument
is the Galileo Optical Image Camera (OIG) installed at the Nasmyth
focus.
Objects:
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RA (2000) DE Designation(s) (File)
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07 00 23 -00 14 15 Cl Biurakan 13 = Cl Berkeley 34 (table2c.dat)
07 16 23 -13 11 50 Cl Berkeley 36 (table2a.dat)
06 22 05 -06 18 59 Cl Berkeley 73 (table2b.dat)
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2a.dat 59 1274 B, V photometry for Berkeley 36
table2b.dat 59 367 B, V photometry for Berkeley 73
table2c.dat 59 999 B, V photometry for Biurakan 13
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Byte-by-byte Description of file: table2a.dat table2b.dat table2c.dat
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Bytes Format Units Label Explanations
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1- 4 I4 --- Seq Sequence number, in the cluster
9- 15 F7.2 pix Xpos x pixel coordinate (1)
20- 26 F7.2 pix Ypos y pixel coordinate (1)
30- 37 F8.3 pix Rad radius from cluster center
43- 48 F6.3 mag Vmag V magnitudes
54- 59 F6.3 mag B-V B-V colour index
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Note (1): 1 pix = 0.144". North is down and east to the right.
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History: Coordinates of Cl Berkeley 73 (09 31 56 -50 13 14) corrected into
06 22 05, -06 18 59 (from erratum 2005A&A...439.1135O 2005A&A...439.1135O) on 11-08-2005
Acknowledgements: Beatriz Barbuy, barbuy(at)astro.iag.usp.br
(End) Patricia Vannier [CDS] 03-Jan-2005