Spectroscopic Gradients in Elliptical Galaxies

dc.creatorGonzalez, J. Jesus
dc.creatorGorgas, Javier
dc.date1995-07-12
dc.date.accessioned2026-07-07T02:19:54Z
dc.date.available2026-07-07T02:19:54Z
dc.descriptionPreliminary results based on a large compilation of line-strength profiles are presented and discussed. Elliptical galaxies (Es) with strong central Mg$_2$ show steeper line-strength gradients. These galaxies are more massive and have higher velocity dispersions, note nevertheless, that the Mg$_2$ gradient correlates better with central Mg$_2$ than with any other global or structural parameter. This correlation, and the fact that Mg$_2$ measures $Z/Z_\odot$ together with the [Mg/Fe] abundances among Es, are of extreme importance for the use of the central Mg$_2-σ$ relation as a reflection of a mass-metallicity relation. Spectroscopic gradients arise mainly from a radial decrease in mean stellar metallicity. However, the Mg$_2$ and $<{\rm Fe}>$ gradients do not correlate within measuring errors, indicating that something else, besides metallicity, is also varying within a galaxy. H$β$ gradients indicate that the centers of Es tend to look spectroscopically ``younger'' than their stellar populations further out.
dc.description10 pages, compressed uuencoded PostScript including figures. To appear on "Fresh Views on Elliptical Galaxies", ASP Conf. Ser., eds Buzzoni, A., and Renzini, A
dc.identifierhttps://arxiv.org/abs/astro-ph/9507042
dc.identifierhttp://arxiv.org/abs/astro-ph/9507042
dc.identifier.urihttp://salesiana.dossiersoluciones.com/handle/123456789/10049
dc.subjectAstrophysics
dc.titleSpectroscopic Gradients in Elliptical Galaxies
dc.typetext

Files

Collections