J/MNRAS/385/1270 Age-metallicity relation via photometry (Li+, 2008)
Colour pairs for constraining the age and metallicity of stellar populations.
Li Z., Han Z.
<Mon. Not. R. Astron. Soc., 385, 1270-1278 (2008)>
=2008MNRAS.385.1270L 2008MNRAS.385.1270L
ADC_Keywords: Galaxies, photometry ; Abundances, [Fe/H] ; Stars, ages
Keywords: galaxies: elliptical and lenticular, cD - galaxies: photometry -
galaxies: stellar content
Abstract:
Using a widely used stellar-population synthesis model, we study
the possibility of using pairs of AB system colours to break the
well-known stellar age-metallicity degeneracy and to give constraints
on two luminosity-weighted stellar-population parameters (age
and metallicity). We present the relative age and metallicity
sensitivities of the AB system colours that relate to the u, B, g, V,
r, R, i, I, z, J,H and K bands, and we quantify the ability of various
colour pairs to break the age-metallicity degeneracy.
The results also show that the stellar ages and metallicities of
galaxies observed by the Sloan Digital Sky Survey and the Two-Micron
All-Sky Survey can be estimated via photometry data.
Description:
The stellar metallicities and ages of 1646 galaxies selected from SDSS
and 2MASS are listed. The results are measured via (u-r) and (r-K)
colours. The photometry data are taken from SDSS and 2MASS. The simple
stellar population model of Bruzual & Charlot (2003MNRAS.344.1000B 2003MNRAS.344.1000B)
are used for fit.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
metage.dat 93 1646 Basic information and stellar metallicities and
ages of galaxies
--------------------------------------------------------------------------------
See also:
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
http://sdss.org : SDSS Home page
J/A+A/471/795 : Stellar population ages & metallicities from colors (Li+, 2007)
Byte-by-byte Description of file: metage.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
2- 19 A18 --- objID Unique SDSS identifier of galaxies
21- 31 F11.7 deg RAdeg J2000 right ascension in decimal degrees
33- 43 F11.7 deg DEdeg J2000 declination in decimal degrees
46- 50 F5.3 --- z Redshift
53- 57 F5.3 --- e_z Uncertainty of redshift
59- 64 F6.4 --- Zbest Best-fit stellar metallicity
66- 71 F6.4 --- Zlow Lower limit for possible stellar metallicity (1)
73- 78 F6.4 --- Zup Upper limit for possible stellar metallicity (1)
80- 83 F4.1 Gyr tbest Best-fit stellar age
85- 88 F4.1 Gyr tlow Lower limit for possible stellar age (1)
90- 93 F4.1 Gyr tup Upper limit for possible stellar age (1)
--------------------------------------------------------------------------------
Note (1): The lower and upper limits for stellar metallicity and age correspond
to the uncertainties in the two colours used for fit.
--------------------------------------------------------------------------------
Acknowledgements:
Zhongmu Li, zhongmu.li(at)gmail.com
(End) Zhongmu Li [YNAO, China], Patricia Vannier [CDS] 23-Jun-2008