The Gaia -ESO Survey: Metallicity and kinematic trends in the Milky Way bulge

dc.contributor.authorRojas-Arriagada, A.
dc.contributor.authorRecio-Blanco, A.
dc.contributor.authorHill, V.
dc.contributor.authorDe Laverny, P.
dc.contributor.authorSchultheis, M.
dc.contributor.authorBabusiaux, C.
dc.contributor.authorZoccali, M.
dc.contributor.authorMinniti, D.
dc.contributor.authorGonzalez, O.A.
dc.contributor.authorFeltzing, S.
dc.contributor.authorGilmore, G.
dc.contributor.authorRandich, S.
dc.contributor.authorVallenari, A.
dc.contributor.authorAlfaro, E.J.
dc.contributor.authorBensby, T.
dc.contributor.authorBragaglia, A.
dc.contributor.authorFlaccomio, E.
dc.contributor.authorLanzafame, A.C.
dc.contributor.authorPancino, E.
dc.contributor.authorSmiljanic, R.
dc.contributor.authorBergemann, M.
dc.contributor.authorCostado, M.T.
dc.contributor.authorDamiani, F.
dc.contributor.authorHourihane, A.
dc.contributor.authorJofré, P.
dc.contributor.authorLardo, C.
dc.contributor.authorMagrini, L.
dc.contributor.authorMaiorca, E.
dc.contributor.authorMorbidelli, L.
dc.contributor.authorSbordone, L.
dc.contributor.authorWorley, C.C.
dc.contributor.authorZaggia, S.
dc.contributor.authorWyse, R.
dc.date.accessioned2023-05-18T22:27:57Z
dc.date.available2023-05-18T22:27:57Z
dc.date.issued2014-09
dc.descriptionIndexación: Scopus.es
dc.description.abstractAims. Observational studies of the Milky Way bulge are providing increasing evidence of its complex chemo-dynamical patterns and morphology. Our intent is to use the iDR1 Gaia-ESO Survey (GES) data set to provide new constraints on the metallicity and kinematic trends of the Galactic bulge, exploring the viability of the currently proposed formation scenarios. Methods. We analyzed the stellar parameters and radial velocities of ∼1200 stars in five bulge fields wich are located in the region −10◦ < l < 7 ◦ and −10◦ < b < −4 ◦ . We use VISTA Variables in the Via Lactea (VVV) photometry to verify the internal consistency of the atmospheric parameters recommended by the consortium. As a by-product, we obtained reddening values using a semi-empirical Teff-color calibration. We constructed the metallicity distribution functions and combined them with photometric and radial velocity data to analyze the properties of the stellar populations in the observed fields. Results. From a Gaussian decomposition of the metallicity distribution functions, we unveil a clear bimodality in all fields, with the relative size of components depending of the specific position on the sky. In agreement with some previous studies, we find a mild gradient along the minor axis (−0.05 dex/deg between b = −6 ◦ and b = −10◦ ) that arises from the varying proportion of metal-rich and metal-poor components. The number of metal-rich stars fades in favor of the metal-poor stars with increasing b. The K-magnitude distribution of the metal-rich population splits into two peaks for two of the analyzed fields that intersects the near and far branches of the X-shaped bulge structure. In addition, two lateral fields at (l, b) = (7, −9) and (l, b) = (−10, −8) present contrasting characteristics. In the former, the metallicity distribution is dominated by metal-rich stars, while in the latter it presents a mix of a metal-poor population and and a metal-intermediate one, of nearly equal sizes. Finally, we find systematic differences in the velocity dispersion between the metal-rich and the metal-poor components of each field. Conclusions. The iDR1 bulge data show chemo-dynamical distributions that are consistent with varying proportions of stars belonging to (i) a metal-rich boxy/peanut X-shaped component, with bar-like kinematics; and (ii) a metal-poor more extended rotating structure with a higher velocity dispersion that dominates far from the Galactic plane. These first GES data already allow studying the detailed spatial dependence of the Galactic bulge populations, thanks to the analysis of individual fields with relatively high statistics.es
dc.description.urihttps://www.aanda.org/articles/aa/full_html/2014/09/aa24121-14/aa24121-14.html
dc.identifier.citationAstronomy and Astrophysics. Volume 569. 1 September 2014. Article number A103es
dc.identifier.doiDOI: 10.1051/0004-6361/201424121
dc.identifier.issn0004-6361
dc.identifier.urihttps://repositorio.unab.cl/xmlui/handle/ria/49794
dc.language.isoenes
dc.publisherEDP Scienceses
dc.rights.licenseAtribution 4.0 International (CC BY 4.0)
dc.rights.urihttps://creativecommons.org/licenses/by/4.0/deed.es
dc.subjectGalaxy: Formationes
dc.subjectGalaxy: Abundanceses
dc.subjectGalaxy: Bulgees
dc.subjectGalaxy: stellar contentes
dc.subjectStars: Abundanceses
dc.titleThe Gaia -ESO Survey: Metallicity and kinematic trends in the Milky Way bulgees
dc.typeArtículoes
Archivos
Bloque original
Mostrando 1 - 1 de 1
No hay miniatura disponible
Nombre:
Rojas-Arriagada_The_Gaia -ESO_Survey_Metallicity_and.pdf
Tamaño:
3.9 MB
Formato:
Adobe Portable Document Format
Descripción:
TEXTO COMPLETO EN INGLÉS
Bloque de licencias
Mostrando 1 - 1 de 1
No hay miniatura disponible
Nombre:
license.txt
Tamaño:
1.71 KB
Formato:
Item-specific license agreed upon to submission
Descripción: