New $\vec{UBVRI}$ color distributions in E-type galaxies

Autor:	Thais Eunice Pires Idiart, J. A. de Freitas Pacheco, R. Michard
Rok vydání:	2003
Předmět:	Physics Sample average Space and Planetary Science Calibration (statistics) Metallicity Line strength Velocity dispersion Astronomy and Astrophysics Coma (optics) Astrophysics Type (model theory) Galaxy
Zdroj:	Astronomy & Astrophysics. 398:949-957
ISSN:	1432-0746 0004-6361
DOI:	10.1051/0004-6361:20021718
Popis:	Central and mean metallicities are calculated for a sample of 40 early-type galaxies, whose color gradients were reported in a previous paper (Idiart et al.2002). The present color-metallicity calibration was derived from a grid of evolutionary models which fit the color-magnitude sequence of ellipticals in Coma and Virgo clusters. The mean metallicity gradient derived from our data is $(\Delta{\rm [Fe/H]}/\Delta \log r) = -0.26 \pm 0.08$ and the mean sample average metallicity is ${ } = 0.01 \pm 0.11$ (rmsd). Central and mean metallicities are correlated with the central velocity dispersion, consistent with the interpretation by metallicity variations of the color-magnitude sequence and of color gradients. Age effects are also discussed, in particular concerning the interpretation of the H β line strength in those objects.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::c47c2611779cf414fd8b936c2d542e23 https://doi.org/10.1051/0004-6361:20021718 Zobrazit plný text záznamu