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. =2005A&A...429..607O (SIMBAD/NED BibCode) ================================================================================ 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: ------------------------------------------------------- RA (2000) DE Designation(s) ------------------------------------------------------- 07 16 23 -13 11 50 Cl Berkeley 36 09 31 56 -50 13 14 Cl Berkeley 73 07 00 23 -00 14 15 Cl Biurakan 13 = Cl Berkeley 34 ------------------------------------------------------- File Summary: -------------------------------------------------------------------------------- FileName Lrecl Records Explanations -------------------------------------------------------------------------------- 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 -------------------------------------------------------------------------------- Byte-by-byte Description of file: table2a.dat table2b.dat table2c.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 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 -------------------------------------------------------------------------------- Note (1): 1 pix = 0.144". North is down and east to the right. -------------------------------------------------------------------------------- Acknowledgements: Beatriz Barbuy, barbuy(at)astro.iag.usp.br ================================================================================ (End) Patricia Vannier [CDS] 03-Jan-2005