Access to Astronomical Catalogues

← Click to display the menu
J/ApJ/700/523     Galactic star clusters in SDSS. II. Colors.        (An+, 2009)

Galactic globular and open clusters in the Sloan digital sky survey. II. Test of theoretical stellar isochrones. An D., Pinsonneault M.H., Masseron T., Delahaye F., Johnson J.A., Terndrup D.M., Beers T.C., Ivans I.I., Ivezic Z. <Astrophys. J., 700, 523-544 (2009)> =2009ApJ...700..523A
ADC_Keywords: Clusters, globular ; Associations, stellar ; Photometry, SDSS ; Effective temperatures ; Models ; Abundances Keywords: globular clusters: individual (M3, M5, M13, M15, M71, M92) - Hertzsprung-Russell (HR) diagram - open clusters and associations: individual (M67, NGC 6791) - stars: evolution - surveys Abstract: We perform an extensive test of theoretical stellar models for main-sequence (MS) stars in ugriz, using cluster fiducial sequences obtained in the previous paper of this series. We generate a set of isochrones using the Yale Rotating Evolutionary Code with updated input physics, and derive magnitudes and colors in ugriz from MARCS model atmospheres. These models match cluster MSs over a wide range of metallicity within the errors of the adopted cluster parameters. However, we find a large discrepancy of model colors at the lower MS (Teff≲4500K) for clusters at and above solar metallicity. We also reach similar conclusions using the theoretical isochrones of Girardi et al. and Dotter et al., but our new models are generally in better agreement with the data. Using our theoretical isochrones, we also derive MS-fitting distances and turnoff ages for five key globular clusters, and demonstrate the ability to derive these quantities from photometric data in the Sloan Digital Sky Survey. In particular, we exploit multiple color indices (g-r, g-i, and g-z) in the parameter estimation, which allows us to evaluate internal systematic errors. Our distance estimates, with an error of σ(m-M)=0.03-0.11mag for individual clusters, are consistent with Hipparcos-based subdwarf-fitting distances derived in the Johnson-Cousins or Stromgren photometric systems. Description: Cluster photometry was obtained in Paper I (An et al., 2008ApJS..179..326A) from the SDSS ugriz imaging data. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table5.dat 51 2107 Bolometric corrections and synthetic colors in ugriz
See also: J/MNRAS/405/1711 : VRIg'i' photometry of 7 M15 giants (Mcdonald+, 2010) J/A+A/486/941 : Abundances in M71 (NGC 6838) (Alves-Brito+, 2008) J/AJ/133/1585 : Stromgren photometry in NGC 6791 (Anthony-Twarog+, 2007) J/A+A/320/757 : M3 stars CCD photometry (Ferraro+ 1997) J/AJ/107/1745 : HST UVI photometry of M15. II. (Yanny+, 1994) Byte-by-byte Description of file: table5.dat
Bytes Format Units Label Explanations
1- 4 F4.1 [Sun] [Fe/H] Metallicity 6- 8 F3.1 [Sun] [a/Fe] log(α/Fe) abundance ratio 10- 13 I4 K Teff Effective temperature 15- 17 F3.1 [cm/s2] log(g) Log of surface gravity 19- 24 F6.3 mag BC Bolometric correction for r band 26- 30 F5.3 mag u-g The SDSS (u-g) color index (1) 32- 37 F6.3 mag g-r The SDSS (g-r) color index (1) 39- 44 F6.3 mag g-i The SDSS (g-i) color index (1) 46- 51 F6.3 mag g-z The SDSS (g-z) color index (1)
Note (1): The AB corrections for the SDSS magnitudes and empirical color corrections are not applied.
History: From electronic version of the journal References: An et al. Paper I. 2008ApJS..179..326A
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 19-Jul-2011
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

catalogue service

© UDS/CNRS

Contact