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J/ApJ/663/296 UBV(RI)c phot. of omega Cen (NGC5139) subgiants (Villanova+, 2007)

The multiplicity of the subgiant branch of ω Centauri: evidence for prolonged star formation. Villanova S., Piotto G., King I.R., Anderson J., Bedin L.R., Gratton R.G., Cassisi S., Momany Y., Bellini A., Cool A.M., Recio-Blanco A., Renzini A. <Astrophys. J., 663, 296-314 (2007)> =2007ApJ...663..296V
ADC_Keywords: Clusters, globular ; Stars, giant ; Photometry, HST ; Photometry, UBVRI Keywords: Galaxy: abundances - globular clusters: individual (NGC 5139) - Hertzsprung-Russell diagram Abstract: We combine spectroscopic and photometric data for subgiant stars of ω Cen to extract results that neither data set could have provided on its own. GIRAFFE@VLT spectra of 80 stars at R=6400 give metallicities for all of them and abundances of C, N, Ca, Ti, and Ba for a subset of them. The photometric data, which have unusually high accuracy, come from a ∼10x10arcmin2 mosaic of HST ACS images centered on the cluster center and on multicolor images of a ∼34x33arcmin2 field, taken with the camera. Stars with [Fe/H]←1.25 have a large magnitude spread on the flat part of the sub-giant branch (SGB). We interpret this as empirical evidence for an age spread, and from theoretical isochrones we derive a relative age for each star. Description: Our photometric Hubble Space Telescope (HST) study is based on a mosaic of 3x3 HST Advanced Camera for Surveys (ACS) Wide Field Channel (WFC) fields taken in GO-9442 (PI Cool). The ground-based component of our photometry is based on 187 images taken from 1999 to 2003 with the camera (hereafter WFI). Exposure times cover the range 5-1800s in Johnson U, B, and V, and in Cousins RC and IC, plus some observations with the 665 and 658nm narrowband filters. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table1.dat 57 22 Stars observed at HST table2.dat 72 57 Stars observed at WFI
See also: J/AJ/108/1350 : Omega Cen FUV photometry (Whitney+, 1994) J/AJ/114/1087 : Omega Cen radial velocities (Mayor+ 1997) J/AJ/119/1225 : Stroemgren photometry of Omega Cen & NGC 6397 (Hughes+ 2000) J/AJ/119/1824 : Caby photometry of Ω Centauri (Rey+, 2000) J/A+A/400/521 : Omega Cen XMM observations (Gendre+, 2003) J/A+A/420/173 : JK photometry of Omega Cen red giants (Sollima+, 2004) J/AJ/127/980 : vby and BVI photometry of Omega Cen giants (Hughes+, 2004) J/MNRAS/357/265 : BVI photometry of omega Cen red giants (Sollima+, 2005) J/ApJ/661/L155 : Radial velocities Rgb stars in omega Cen (Pancino+, 2007) J/A+A/445/503 : Radial velocities in Omega Cen (NGC5139) (Reijns+, 2006) J/ApJ/654/915 : Deep FORS1 BR photometry of omega Cen (Sollima+, 2007) J/MNRAS/382/1353 : Spectral atlas of omega Cen post-MS stars (Van Loon+, 2007) J/AJ/135/1395 : omega Cen Spitzer photometry (Boyer+, 2008) Byte-by-byte Description of file: table1.dat
Bytes Format Units Label Explanations
1- 5 I5 --- PKD Sequential number, Cl* NGC 5139 PKD NNNNN in Simbad 7- 16 F10.6 deg RAdeg Right ascension in decimal degrees (J2000.0) 18- 27 F10.6 deg DEdeg Declination in decimal degrees (J2000.0) 29- 33 F5.2 mag F435W HST F435W magnitude 35- 38 F4.2 mag F435W-F625W HST F435W-F625W colour index 40- 44 F5.2 mag Vmag Johnson V magnitude 46- 48 I3 km/s HRV Heliocentric radial velocity 50- 53 I4 K Teff Effective temperature 55- 57 F3.1 [cm/s2] logg Surface gravity
Byte-by-byte Description of file: table2.dat
Bytes Format Units Label Explanations
1- 5 I5 --- PKD Sequential number, Cl* NGC 5139 PKD NNNNN in Simbad 7- 16 F10.6 deg RAdeg Right ascension in decimal degrees (J2000.0) 18- 27 F10.6 deg DEdeg Declination in decimal degrees (J2000.0) 29- 33 F5.2 mag Vmag Johnson V magnitude 35- 38 F4.2 mag B-V Johnson B-V colour index 40- 43 F4.2 mag V-Ic Johnson-Cousins V-I colour index 45- 48 F4.2 mag V-Rc Johnson-Cousins V-R colour index 50- 52 I3 km/s HRV Heliocentric radial velocity 54- 57 I4 K Teff Effective temperature 59- 61 F3.1 [cm/s2] logg Surface gravity 63- 67 F5.2 [-] [Fe/H] Metallicity 69- 72 F4.2 Gyr Age Estimated age
History: From electronic version of the journal
(End) Patricia Vannier [CDS] 14-Aug-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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