J/MNRAS/368/471 Berkeley 32 BVI photometry and spectroscopy (D'Orazi+, 2006)
The old anticentre open cluster Berkeley 32:
membership and fundamental parameters.
D'Orazi V., Bragaglia A., Tosi M., Fabrizio L.D., Held E.V.
<Mon. Not. R. Astron. Soc., 368, 471-478 (2006)>
=2006MNRAS.368..471D 2006MNRAS.368..471D
ADC_Keywords: Clusters, open ; Photometry, UBVRI ; Radial velocities
Keywords: Hertzsprung-Russell (HR) diagram -
open clusters and associations: general -
open clusters and associations: individual: Berkeley 32
Abstract:
We have obtained medium- and low-resolution spectroscopy and BVI
CCD imaging of Berkeley 32, an old open cluster which lies in the
anticentre direction. From the radial velocities of 48 stars in the
cluster direction, we found that 31 of them, in crucial evolutionary
phases, are probable cluster members, with an average radial velocity
of +106.7(sigma=8.5)km/s .
From isochrone fitting to the colour-magnitude diagrams of Berkeley
32, we have obtained an age of 6.3Gyr, (m-M)0=12.48 and E(B-V)=0.10.
The best fit is obtained with Z=0.008. A consistent distance,
(m-M)0~=12.6±0.1, has been derived from the mean magnitude of
red clump stars with confirmed membership; we may assume
(m-M)0~=12.55±0.1.
The colour-magnitude diagram of the nearby field observed to check
for field stars contamination looks intriguingly similar to that of
the Canis Major overdensity.
Description:
Our data were acquired at the Italian Telescopio Nazionale Galileo, on
the Canary Islands, using DOLORES (device optimized for the low
resolution), a focal reducer capable of imaging and low-resolution
spectroscopy, on UT 2000 November 26 and 2004 February 14.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table.dat 92 2031 BVI photometry (from WEBDA)
table4.dat 80 47 Radial velocities of stars in Be 32
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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 --- DBT Star sequential number,
Cl* Berkeley 32 DBT NNNN in Simbad
6- 11 F6.3 mag Bmag ?=99.999 Johnson B magnitude
13- 17 F5.3 mag e_Bmag ?=9.999 rms uncertainty on Bmag
19- 24 F6.3 mag Vmag1 ?=99.999 Johnson V magnitude calculated
from B-V colour index
26- 31 F6.3 mag Vmag2 ?=99.999 Johnson V magnitude calculated
from V-I colour index
33- 37 F5.3 mag e_Vmag ?=9.999 rms uncertainty on Vmag
39- 44 F6.3 mag Imag ?=99.999 Cousins I magnitude
46- 50 F5.3 mag e_Imag ?=9.999 rms uncertainty on Imag
52- 59 F8.3 pix Xpos X position
61- 68 F8.3 pix Ypos Y position
70 I1 h RAh Right ascension (J2000)
72- 73 I2 min RAm Right ascension (J2000)
75- 80 F6.3 s RAs Right ascension (J2000)
82 A1 --- DE- Declination sign (J2000)
83 I1 deg DEd Declination (J2000)
85- 86 I2 arcmin DEm Declination (J2000)
88- 92 F5.2 arcsec DEs Declination (J2000)
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 4 I4 --- DBT Star sequential number,
Cl* Berkeley 32 DBT NNNN in Simbad
6- 8 I3 --- KM ? Kaluzny & Mazur (1991AcA....41..167K 1991AcA....41..167K) number,
Cl* Berkeley 32 KM NNN in Simbad
10- 13 I4 --- RS ? Richtler & Sagar (2001BASI...29...53R 2001BASI...29...53R) number,
Cl* Berkeley 32 RS NNNN in Simbad
15 I1 h RAh Right ascension (J2000)
17- 18 I2 min RAm Right ascension (J2000)
20- 25 F6.3 s RAs Right ascension (J2000)
27 A1 --- DE- Declination sign (J2000)
28 I1 deg DEd Declination (J2000)
30- 31 I2 arcmin DEm Declination (J2000)
33- 37 F5.2 arcsec DEs Declination (J2000)
39- 44 F6.2 km/s HRV Heliocentric radial velocity
46- 50 F5.2 km/s e_HRV Standard deviation from the mean HRV
52- 54 I3 km/s RVSFJ ? Scott et al. (1995AJ....109.1706S 1995AJ....109.1706S)
radial velocity
56- 61 F6.3 mag Bmag Johnson B magnitude (1)
63- 68 F6.3 mag Vmag Johnson V magnitude (1)
70- 75 F6.3 mag Imag ? Cousins I magnitude (1)
77 A1 --- Mm [CF] Membership status:
C for cluster member and F for field stars
79- 80 A2 --- Mask Mask number (M1 or M2)
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Note (1): Magnitudes come from our catalogue (except for star 2689 -
which we measured only in B and I- where B, V come from
Kaluzny & Mazur, 1991AcA....41..167K 1991AcA....41..167K).
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History:
* 10-May-2010: From electronic version of the journal
* 08-Aug-2010: in table4, for DBT=18: KM=351 removed, following an
annotation in Simbad about Cl* Berkeley 32 RS 1741
(End) Fabienne Woelfel, Patricia Vannier [CDS] 10-May-2010