J/MNRAS/408/1147 UBVI photometry of 4 open clusters (Piatti+, 2010)
First CCD UBVI photometric analysis of four moderately young open clusters in
the third galactic quadrant.
Piatti A.E., Claria J.J., Ahumada A.V.
<Mon. Not. R. Astron. Soc., 408, 1147-1167 (2010)>
=2010MNRAS.408.1147P 2010MNRAS.408.1147P (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, open ; Photometry, UBVRI ; Photometry, CCD
Keywords: techniques: photometric - open clusters and associations: general -
open clusters and associations: individual: NGC 2311 -
open clusters and associations: individual: Trumpler 6 -
open clusters and associations: individual: NGC 2432 -
open clusters and associations: individual: BH 54
Abstract:
We present CCD photometry in the Johnson UBV and Kron-Cousins I
systems down to V∼22.0 for the open clusters NGC 2311, Trumpler 6,
NGC 2432 and BH 54 and their surrounding fields. Trumpler 6 and BH 54
have never been studied before and so we provide, for the first time,
estimates of their fundamental parameters. We obtained
colour-magnitude diagrams (CMDs) and colour-colour diagrams cleaned
from field star contamination by statistically subtracting stars in
terms of spatial density, magnitude and colour distributions. Cluster
angular radii were estimated from star counts in appropriate-sized
boxes distributed throughout the entire observed fields. Using the
cleaned CMDs and colour-colour diagrams, we applied sound photometric
membership criteria to discriminate cluster members from interloper
field stars. The interstellar extinction across the cluster fields
derived from the 100-µm dust emission full-sky maps can be
considered uniform within the quoted uncertainties. The E(B-V) and
E(V-I) colour excesses and the apparent distance moduli of the
clusters were estimated from the fit of the zero-age main-sequence to
the colour-colour diagrams and CMDs, respectively. Cluster ages were
determined from the comparison of the four clusters' CMDs with solar
metallicity theoretical isochrones of the Geneva group. All the
clusters were found to be moderately young objects, their ages ranging
between 60 and 250Myr.
Description:
We obtained images for the cluster sample on the nights of 2000
December 25, 27 and 29 with the UBVIKC filters and a 2048x2048-pixel
Tektronix CCD attached to the 0.9-m telescope (scale 0.4arcsec/pix) at
Cerro Tololo Inter-American Observatory (CTIO), Chile. Its field of
view is 13.6x13.6arcmin2.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 69 4 Basic parameters of the four studied OCs
table4.dat 98 945 CCD UBVI data for stars in the field of NGC 2311
table5.dat 98 3391 CCD UBVI data for stars in the field of Trumpler 6
table6.dat 98 3459 CCD UBVI data for stars in the field of NGC 2432
table7.dat 98 800 CCD UBVI data for stars in the field of BH 54
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See also:
J/A+AS/107/39 : IC 2714 UBV photometry (Claria+ 1994)
J/A+AS/127/423 : VI photometry of Westerlund 1 and 2 (Piatti+ 1998)
J/A+AS/128/131 : UBV photometry of NGC 2323 (Claria+ 1998)
J/ApJS/116/263 : VI photometry of open clusters (Piatti+ 1998)
J/A+A/360/529 : BVI photometry of 4 young open clusters (Piatti+, 2000)
J/A+A/370/931 : BVI photometry of 4 open clusters (Piatti+, 2001)
J/A+A/379/453 : BVI photometry of 5 open cluster candidates (Piatti+, 2001)
J/A+A/388/179 : BVI photometry of two open clusters (Piatti+, 2002)
J/A+A/399/543 : Photometry and Coravel obs. of IC 2488 (Claria+, 2003)
J/A+A/409/541 : UBV photometry of IC 2395 (Claria+, 2003)
J/MNRAS/340/1249 : VIc magnitudes in NGC 2194 (Piatti+, 2003)
J/MNRAS/346/390 : VI and CMT1 photometry of NGC 2627 (Piatti+, 2003)
J/MNRAS/349/641 : VIc, CT1 magnitudes in Trumpler 5 (Piatti+, 2004)
J/A+A/418/979 : VI and CT1 photometry in NGC 2324 field (Piatti+, 2004)
J/A+A/421/991 : CT1 photometry in Tombaugh 1 (Piatti+, 2004)
J/PASP/117/22 : NGC 6318 CCD BVI photometry (Piatti+, 2005)
J/other/NewA/11.262 : BVIc photometry in Lynga 11 (Piatti+, 2006)
J/MNRAS/367/599 : BVI photometry of NGC 5288 (Piatti+, 2006)
J/MNRAS/377/1737 : BVI photometry of NGC 2489 (Piatti+, 2007)
J/MNRAS/397/1073 : UBVI photometry in NGC 2587 (Piatti+, 2009)
J/PASP/122/288 : UBVIKC photometry in NGC 2309 (Piatti+, 2010)
J/MNRAS/402/2720 : 5 Galactic open cluster UBVI photometry (Piatti+, 2010)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- Cluster Cluster name
13- 14 I2 h RAh Right ascension (J2000)
16- 17 I2 min RAm Right ascension (J2000)
19- 20 I2 s RAs Right ascension (J2000)
22 A1 --- DE- Declination sign (J2000)
23- 24 I2 deg DEd Declination (J2000)
26- 27 I2 arcmin DEm Declination (J2000)
29- 30 I2 arcsec DEs Declination (J2000)
32- 37 F6.2 deg GLON Galactic longitude
39- 43 F5.2 deg GLAT Galactic latitude
45- 50 A6 --- Class Trumpler class
51- 54 F4.1 arcmin Diam Angular diameter
56- 59 I4 --- Nmeas Number of measured stars
60- 62 I3 --- Ninf Number of inferred cluster stars
64- 69 A6 --- FileName Name of the table with photometry
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Byte-by-byte Description of file: table[4567].dat
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Bytes Format Units Label Explanations
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1- 6 I6 --- Seq Sequential number within the cluster
9- 16 F8.3 pix Xpos X position (1)
19- 26 F8.3 pix Ypos Y position (1)
29- 34 F6.3 mag Vmag Johnson V magnitude
37- 41 F5.3 mag e_Vmag rms uncertainty on Vmag
44 I1 --- o_Vmag Number of observations in Vmag
47- 52 F6.3 mag U-B ?=99.999 Johnson U-B colour index
55- 59 F5.3 mag e_U-B ?=9.999 rms uncertainty on U-B
62 I1 --- o_U-B ?=0 Number of observations in U-B
65- 70 F6.3 mag B-V ?=99.999 Johnson B-V colour index
73- 77 F5.3 mag e_B-V ?=9.999 rms uncertainty on B-V
80 I1 --- o_B-V ?=0 Number of observations in B-V
83- 88 F6.3 mag V-I ?=99.999 Johnson-Cousins V-I colour index
91- 95 F5.3 mag e_V-I ?=9.999 rms uncertainty on V-I
98 I1 --- o_V-I ?=0 Number of observations in V-I
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Note (1): North is up and east is to the left. 1 pix = 0.4arcsec.
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 06-Aug-2013