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J/MNRAS/391/1482    BVIc photometry of Trumpler 20           (Platais+, 2008)

Trumpler 20 - an old and rich open cluster. Platais I., Melo C., Fulbright J.P., Kozhurina-Platais V., Figueira P., Barnes S.A., Mendez R.A. <Mon. Not. R. Astron. Soc., 391, 1482-1488 (2008)> =2008MNRAS.391.1482P
ADC_Keywords: Clusters, open ; Photometry, UBVRI Keywords: stars: abundances - open clusters and associations: individual: Trumpler 20 Abstract: We show that the open cluster Trumpler 20, contrary to the earlier findings, is actually an old Galactic open cluster. New CCD photometry and high-resolution spectroscopy are used to derive the main parameters of this cluster. At [Fe/H]=-0.11 for a single red giant star, the metallicity is slightly subsolar. The best fit to the colour-magnitude diagrams is achieved using a 1.3-Gyr isochrone with convective overshoot. The cluster appears to have a significant reddening at E(B-V)=0.46 (for B0 spectral type), although for red giants this high reddening yields the colour temperature exceeding the spectroscopic Teff by about 200K. Trumpler 20 is a very rich open cluster, containing at least 700 members brighter than MV=+4. It may extend over the field of view available in our study at 20x20arcmin2. Description: In 2008 March 20-22, new photometric CCD observations of Tr 20 were obtained at the CTIO 1-m telescope, operated by the Small and Moderate Aperture Research Telescope System (SMARTS) consortium. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file tr20.dat 67 7166 BVI photometry in Tr 20
See also: J/ApJS/161/118 : Photometry of open clusters (McSwain+, 2005) Byte-by-byte Description of file: tr20.dat
Bytes Format Units Label Explanations
1- 4 I4 --- Seq Sequential number, Cl* Trumpler 20 PMF NNNN in Simbad 6- 14 F9.5 deg RAdeg Right ascension in decimal degrees (J2000) 16- 24 F9.5 deg DEdeg Declination in decimal degrees (J2000) 26- 31 F6.3 mag Vmag Johnson V magnitude 33- 38 F6.3 mag B-V ?=99.999 Johnson B-V colour index 40- 45 F6.3 mag V-Ic ?=99.999 Johnson-Cousins V-Ic colour index 47- 51 F5.3 mag e_Vmag rms uncertainty on Vmag 53- 57 F5.3 mag e_B-V ?=0.000 rms uncertainty on B-V 59- 63 F5.3 mag e_V-Ic ?=0.000 rms uncertainty on V-Ic 65 I1 --- o_B-V Number of observations in B-V 67 I1 --- o_V-Ic Number of observations in V-Ic
History: From electronic version of the journal
(End) Patricia Vannier [CDS] 07-Apr-2009
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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