Browsing by Author "Zoccali, Manuela"
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- Item3D kinematics through the X-shaped Milky Way bulge(2013) Vásquez Godoy, Sergio Osmán.; Zoccali, Manuela; Baffico Haramoto, Rodolfo Maurizio; Minniti, D.
- ItemA Homogeneous Set of Globular Cluster Relative Distances and Reddenings(2005) Recio-Blanco a; Zoccali, Manuela
- ItemA search for substructures near the Galactic plane and bulge using RR Lyrae stars as tracers(2024) Cristi Cambiaso, Nicolas Eduardo; Catelan, Marcio; Zoccali, Manuela; Pontificia Universidad Catolica de Chile. Faculty of Physics. Institute of AstrophysicsUsando estrellas pulsantes de tipo RR Lyrae, hacemos una búsqueda de subestructuras Galácticas ("stellar streams" y cúmulos globulares) en la región del plano Galáctico. Construimos una muestra de estrellas RR Lyrae con valores de distancia y metalicidades. Estudiamos esta muestra con un algoritmo de "clustering" para encontrar grupos de estrellas cercanas y con propiedades similares. Mediante esta búsqueda, recuperamos estructuras conocidas y encontramos posibles nuevas estructuras.
- ItemA spectroscopic survey of thick disc stars outside the solar neighbourhood(2011) Kordopatis, G.; Zoccali, Manuela
- ItemA transiting planet among 23 new near-threshold candidates from the OGLE survey - OGLE-TR-182(2008) Pont, F.; Minniti, D.; Ramírez Alegría, Sebastián A.; Zoccali, Manuela
- ItemAbundances in the Galactic bulge(2008) Barbuy, B.; Zoccali, Manuela; Minniti, D.; Barbuy, B.; Zoccali, Manuela; Minniti, D.
- ItemAbundances of disk and bulge giants from high-resolution optical spectra II. O, Mg, Co, and Ti in the bulge sample(2017) Jönsson, H.; Ryde, N.; Schultheis, M.; Zoccali, Manuela
- ItemAlpha element abundances and gradients in the Milky Way bulge from FLAMES-GIRAFFE spectra of 650 K giants(2011) Gonzalez, O.; Zoccali, Manuela; Minniti, D.
- ItemAssembling a high-precision abundance catalogue of solar twins in GALAH for phylogenetic studies(2024) Walsen, Kurt; Jofre, Paula; Buder, Sven; Yaxley, Keaghan; Das, Payel; Yates, Robert M.; Hua, Xia; Signor, Theosamuele; Eldridge, Camilla; Rojas-Arriagada, Alvaro; Tissera, Patricia B.; Johnston, Evelyn; Aguilera-Gomez, Claudia; Zoccali, Manuela; Gilmore, Gerry; Foley, RobertStellar chemical abundances have proved themselves a key source of information for understanding the evolution of the Milky Way, and the scale of major stellar surveys such as GALAH have massively increased the amount of chemical data available. However, progress is hampered by the level of precision in chemical abundance data as well as the visualization methods for comparing the multidimensional outputs of chemical evolution models to stellar abundance data. Machine learning methods have greatly improved the former; while the application of tree-building or phylogenetic methods borrowed from biology are beginning to show promise with the latter. Here, we analyse a sample of GALAH solar twins to address these issues. We apply The Cannon algorithm to generate a catalogue of about 40 000 solar twins with 14 high precision abundances which we use to perform a phylogenetic analysis on a selection of stars that have two different ranges of eccentricities. From our analyses, we are able to find a group with mostly stars on circular orbits and some old stars with eccentric orbits whose age-[Y/Mg] relation agrees remarkably well with the chemical clocks published by previous high precision abundance studies. Our results show the power of combining survey data with machine learning and phylogenetics to reconstruct the history of the Milky Way.
- ItemC and N abundances of main sequence and subgiant branch stars in NGC 1851(2012) Lardo, C.; Zoccali, Manuela
- ItemCalcium triplet metallicity calibration for stars in the Galactic bulge(2015) Vasquez, S.; Zoccali, Manuela; Hill, V.; Gonzalez, O. A.; Saviane, I.; Rejkuba, M.; Battaglia, G.
- ItemCharacterization of the VVV Survey RR Lyrae Population across the Southern Galactic Plane(2017) Minniti, D.; Dekany, Istvan; Majaess, Daniel; Palma, Tali; Pullen, Joyce; Rejkuba, Marina; Alonso-García, Javier; Catelan, Márcio; Hempel, Maren; Zoccali, Manuela; Contreras Ramos, Rodrigo Andrés; Gonzalez, Oscar A.; Irwin, Mike; Lucas, Philip W.; Saito, Roberto K.; Tissera, Patricia; Valenti, Elena
- ItemChemical abundances of 11 bulge stars from high-resolution, near-IR spectra(2010) Ryde, N.; Minniti, D.; Zoccali, Manuela
- ItemChemical Abundances of the Highly Obscured Galactic Globular Clusters 2MASS GC02 and Mercer 5(2015) Vásquez Godoy, Sergio Osmán.; Zoccali, Manuela
- ItemChemical evolution of fluorine in the bulge High-resolution K-band spectra of giants in three fields(2014) Jonsson, H.; Ryde, N.; Harper, G.; Cunha, K.; Schultheis, M.; Eriksson, K.; Kobayashi, C.; Smith, V.; Zoccali, Manuela
- ItemChemically Dissected Rotation Curves of the Galactic Bulge from Main-sequence Proper Motions(2018) Clarkson, William I.; Calamida, Annalisa; Sahu, Kailash C.; Brown, Thomas M.; Gennaro, Mario; Avila, Roberto J.; Valenti, Jeff; Debattista, Victor P.; Rich, R. Michael; Minniti, D.; Zoccali, Manuela; Aufdemberge, Emily R.
- ItemCobalt and copper abundances in 56 Galactic bulge red giants(2020) Ernandes, H.; Barbuy, B.; Friaca, A. C. S.; Hill, V.; Zoccali, Manuela; Minniti, D.; Renzini, A.; Ortolani, S.
- ItemComparing the properties of the X-shaped bulges of NGC 4710 and the Milky Way with MUSE(2016) Rejkuba, M.; Valenti, E.; Zoccali, Manuela; Coccato, L.; Minniti, D.; Ness, M.; Gonzalez, O.; Gadotti, D.; Debattista, V.
- ItemCool stars in the Galactic center as seen by APOGEE : M giants, AGB stars, and supergiant stars and candidates(2020) Schultheis, M.; Rojas Arriagada, Alvaro; Cunha, K.; Zoccali, Manuela; Chiappini, C.; Zasowski, G.; Queiroz, A. B. A.; Minniti, D.; Fritz, T.; Garcia Hernandez, D. A.; Nitschelm, C.; Zamora, O.; Hasselquist, S.; Fernandez Trincado, J. G.; Munoz, R. .R
- ItemDeep census of variable stars in a VLT/VIMOS field in Carina(2009) Pietrukowicz, Pawel; Minniti, D.; Zoccali, Manuela; Hempel, Maren; Pietrukowicz, Pawel; Minniti, D.; Zoccali, Manuela; Hempel, Maren