dc.contributor.author | Cioni, M-R.L. | |
dc.date.accessioned | 2009-11-25T13:57:11Z | |
dc.date.available | 2009-11-25T13:57:11Z | |
dc.date.issued | 2009-11 | |
dc.identifier.citation | Cioni , M-RL 2009 , ' The metallicity gradient as a tracer of history and structure : the Magellanic Clouds and M33 galaxies ' , Astronomy and Astrophysics , vol. 506 , no. 3 , pp. 1137-1146 . https://doi.org/10.1051/0004-6361/200912138 | |
dc.identifier.issn | 0004-6361 | |
dc.identifier.other | dspace: 2299/4013 | |
dc.identifier.uri | http://hdl.handle.net/2299/4013 | |
dc.description | Original article can be found at: http://www.aanda.org/ Copyright The European Southern Observatory (ESO) DOI: 10.1051/0004-6361/200912138 | |
dc.description.abstract | Context. The stellar metallicity and its gradient place constraints on the formation and evolution of galaxies. Aims. This is a study of the metallicity gradient of the LMC, SMC and M33 galaxies derived from their asymptotic giant branch (AGB) stars. Methods. The [Fe/H] abundance was derived from the ratio between C- and M-type AGB stars and its variation analysed as a function of galactocentric distance. Galaxy structure parameters were adopted from the literature. Results. The metallicity of the LMC decreases linearly as −0.047±0.003 dex kpc−1 out to ∼8 kpc from the centre. In the SMC, [Fe/H] has a constant value of ∼−1.25 ± 0.01 dex up to ∼12 kpc. The gradient of the M33 disc, until ∼9 kpc, is −0.078 ± 0.003 dex kpc−1 while the outer disc/halo, out to ∼25 kpc, has [Fe/H] ∼ −1.7 dex. Conclusions. The metallicity of the LMC, as traced by different populations, bears the signature of two major star forming episodes: the first one constituting a thick disc/halo population and the second one a thin disc and bar due to a close encounter with the Milky Way and SMC. The [Fe/H] of the recent episode supports an LMC origin for the Stream. The metallicity of the SMC supports star formation, ∼3 Gyr ago, as triggered by LMC interaction and sustained by the bar in the outer region of the galaxy. The SMC [Fe/H] agrees with the present-day abundance in the Bridge and shows no significant gradient. The metallicity of M33 supports an “insideout” disc formation via accretion of metal poor gas from the interstellar medium. | en |
dc.format.extent | 283925 | |
dc.language.iso | eng | |
dc.relation.ispartof | Astronomy and Astrophysics | |
dc.title | The metallicity gradient as a tracer of history and structure : the Magellanic Clouds and M33 galaxies | en |
dc.contributor.institution | School of Physics, Astronomy and Mathematics | |
dc.description.status | Peer reviewed | |
rioxxterms.versionofrecord | 10.1051/0004-6361/200912138 | |
rioxxterms.type | Journal Article/Review | |
herts.preservation.rarelyaccessed | true | |