dc.contributor.author | Spolaor, Max | |
dc.contributor.author | Kobayashi, Chiaki | |
dc.contributor.author | Forbes, Duncan A. | |
dc.contributor.author | Couch, Warrick J. | |
dc.contributor.author | Hau, George K. T. | |
dc.date.accessioned | 2011-12-20T13:01:07Z | |
dc.date.available | 2011-12-20T13:01:07Z | |
dc.date.issued | 2010-10-11 | |
dc.identifier.citation | Spolaor , M , Kobayashi , C , Forbes , D A , Couch , W J & Hau , G K T 2010 , ' Early-type galaxies at large galactocentric radii - II. Metallicity gradients and the [Z/H]-mass, [alpha/Fe]-mass relations ' , Monthly Notices of the Royal Astronomical Society , vol. 408 , no. 1 , pp. 272-292 . https://doi.org/10.1111/j.1365-2966.2010.17080.x | |
dc.identifier.issn | 0035-8711 | |
dc.identifier.other | PURE: 493546 | |
dc.identifier.other | PURE UUID: 2224c22d-700e-45f4-93d2-402f3804588c | |
dc.identifier.other | WOS: 000283118100019 | |
dc.identifier.other | Scopus: 78649396075 | |
dc.identifier.other | ORCID: /0000-0002-4343-0487/work/62750461 | |
dc.identifier.uri | http://hdl.handle.net/2299/7411 | |
dc.description.abstract | We present the results of a study of stellar population properties at large galactocentric radii of 14 low-mass early-type galaxies in the Fornax and Virgo clusters. We derive radial profiles of age, total metallicity [Z/H] and [alpha/Fe] abundance ratios out to similar to 1-3 effective radii by using nearly all of the Lick/IDS absorption-line indices in comparison to recent single stellar population models. We extend our study to higher galaxy mass via a novel literature compilation of 37 early-type galaxies, which provides stellar population properties out to one effective radius. We find that metallicity gradients correlate with galactic mass, and the relationship shows a sharp change in slope at a dynamical mass of similar to 3.5 x 10(10) M-circle dot. The central and mean values of the stellar population parameters (measured in r <= r(e)/8 and at r = r(e), respectively) define positive mass trends. We suggest that the low metallicities, almost solar [alpha/Fe] ratios and the tight mass-metallicity gradient relation displayed by the low-mass galaxies are indicative of an early star-forming collapse with extended (i.e. >= 1 Gyr), low-efficiency star formation, and mass-dependent galactic outflows of metal-enriched gas. The flattening of metallicity gradients in high-mass galaxies and the broad scatter of the relationship are attributed to merger events. The high metallicities and supersolar abundances shown by these galaxies imply a rapid, high efficiency star formation. The observed [Z/H]-mass and [alpha/Fe]-mass relationships can be interpreted as a natural outcome of an early star-forming collapse. However, we find that hierarchical galaxy formation models implementing mass-dependent star formation efficiency, varying initial mass function, energy feedback via active galactic nucleus and the effects due to merger-induced starbursts can also reproduce both our observed relationships. | en |
dc.format.extent | 21 | |
dc.language.iso | eng | |
dc.relation.ispartof | Monthly Notices of the Royal Astronomical Society | |
dc.subject | galaxies: abundances | |
dc.subject | galaxies: dwarf | |
dc.subject | galaxies: elliptical and lenticular, cD | |
dc.subject | galaxies: evolution | |
dc.subject | galaxies: formation | |
dc.subject | galaxies: stellar content | |
dc.subject | STELLAR POPULATION-MODELS | |
dc.subject | SPATIALLY-RESOLVED SPECTROSCOPY | |
dc.subject | SURFACE BRIGHTNESS FLUCTUATIONS | |
dc.subject | SPH CHEMODYNAMICAL SIMULATION | |
dc.subject | ABSORPTION-LINE STRENGTHS | |
dc.subject | STAR-FORMATION HISTORIES | |
dc.subject | FUNDAMENTAL-PLANE-SURVEY | |
dc.subject | ACTIVE GALACTIC NUCLEI | |
dc.subject | RED-SEQUENCE GALAXIES | |
dc.subject | ELLIPTIC GALAXIES | |
dc.title | Early-type galaxies at large galactocentric radii - II. Metallicity gradients and the [Z/H]-mass, [alpha/Fe]-mass relations | en |
dc.contributor.institution | Centre for Astrophysics Research | |
dc.contributor.institution | School of Physics, Engineering & Computer Science | |
dc.contributor.institution | Department of Physics, Astronomy and Mathematics | |
dc.description.status | Peer reviewed | |
rioxxterms.version | AM | |
rioxxterms.versionofrecord | https://doi.org/10.1111/j.1365-2966.2010.17080.x | |
rioxxterms.type | Journal Article/Review | |
herts.preservation.rarelyaccessed | true | |