Subvenciones relacionadas:
General
La espectroscopía de estrellas nos permite determinar las propiedades y composiciones químicas de las mismas. A partir de esta información para estrellas de diferente edad en la Vía Láctea es posible reconstruir la evolución química de la Galaxia, así como el origen de los elementos más pesados que el boro, forjados principalmente en los interiores estelares. También es posible estudiar la formación estelar, y la de la propia Galaxia, a través de la huella que deja el potencial Galáctico en las órbitas de las estrellas, y de las distribuciones de masa, edad y la abundancia de elementos pesados.
La obtención de espectros con alta resolución espectral, apropiados para estudios de la composición química, requiere instrumentación sofisticada y eficiente. Esto es especialmente cierto en investigaciones en las que se necesitan extensas muestras de estrellas, que exigen observar cientos, o incluso miles de fuentes de forma simultánea. El procesado y análisis de los datos debe ser automatizado para ser igualmente eficiente.
La interpretación de los espectros se basa en modelos físicos de las atmósferas de las estrellas, de donde se escapa la luz que observamos. Los ingredientes fundamentales para la construcción de estos modelos son la dinámica de fluidos, y las propiedades de los átomos, iones y moléculas, especialmente en lo que se refiere a sus interacciones con la radiación que proviene del interior estelar. Una vez que se tiene un modelo plausible, es posible calcular de forma detallada cómo se propaga la radiación a través de la atmósfera estelar, y el espectro emergente, para, de forma iterativa, compararlo con las observaciones y refinar el modelo.
Este Proyecto incluye tres diferentes frentes de investigación:
- La mejora de los modelos de atmósfera y las simulaciones de espectros estelares.
- El desarrollo de herramientas para la obtención, reducción y el análisis de observaciones espectroscópicas, y en particular para la determinación de abundancias químicas en estrellas.
- El diseño, preparación, y ejecución de estudios espectroscópicos de estrellas con el fin de entender a) los aspectos más relevantes de la física de las atmósferas estelares, b) la formación y evolución de las estrellas, c) el origen de los elementos químicos y d) la formación, estructura y evolución química de la Vía Láctea.
Miembros
Resultados
- Completar la instalación y pruebas de HORuS en GTC
- Descubrir dos nuevas estrellas con abundancias de hierro inferiores a 100.000 veces el valor solar
- Completar la clasificación de los espectros de APOGEE con K-means
- Publicar una colección completa de espectros modelo para estrellas O a M
- Identificar la huella de la difusión química en las atmósferas de estrellas del cúmulo M67
Actividad científica
Publicaciones relacionadas
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ESPRESSO observations of HE 0107−5240 and other CEMP-no stars with [Fe/H] ≤ -4.5
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122022 -
Overview of the Instrumentation for the Dark Energy Spectroscopic Instrument
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112022 -
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The Gaia-ESO Public Spectroscopic Survey: Implementation, data products, open cluster survey, science, and legacy,★
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102022 -
Non-LTE abundance corrections for late-type stars from 2000 Å to 3 µm. I. Na, Mg, and Al
Context. It is well known that cool star atmospheres depart from local thermodynamic equilibrium (LTE). Making an accurate abundance determination requires taking those effects into account, but the necessary non-LTE (hereafter NLTE) calculations are often lacking. Aims: Our goal is to provide detailed estimates of NLTE effects for FGK type stars
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92022 -
HD 23472: a multi-planetary system with three super-Earths and two potential super-Mercuries
Context. Comparing the properties of planets orbiting the same host star, and thus formed from the same accretion disc, helps in constraining theories of exoplanet formation and evolution. As a result, the scientific interest in multi-planetary systems is growing with the increasing number of detections of planetary companions. Aims: We report the
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Information content of BP/RP spectra in Gaia DR3
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BACCHUS Analysis of Weak Lines in APOGEE Spectra (BAWLAS)
Elements with weak and blended spectral features in stellar spectra are challenging to measure and require specialized analysis methods to precisely measure their chemical abundances. In this work, we have created a catalog of approximately 120,000 giants with high signal-to-noise Apache Point Observatory Galactic Evolution Experiment (APOGEE) Data
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92022 -
White Dwarf Binaries across the H-R Diagram
We created the APOGEE-GALEX-Gaia catalog to study white dwarf (WD) binaries. This database aims to create a minimally biased sample of WD binary systems identified from a combination of GALEX, Gaia, and APOGEE data to increase the number of WD binaries with orbital parameters and chemical compositions. We identify 3414 sources as WD binary
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102022 -
Absolute dimensions and apsidal motion of the eclipsing binaries V889 Aquilae and V402 Lacertae
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Photometric and spectroscopic study of the burst-like brightening of two Gaia-alerted young stellar objects
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HORuS transmission spectroscopy and revised planetary parameters of KELT-7 b
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Interpolation of spectra from 3D model atmospheres
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52022 -
SEGUE-2: Old Milky Way Stars Near and Far
The Sloan Extension for Galactic Understanding and Exploration 2 (SEGUE-2) obtained 128,288 low-resolution spectra (R ~ 1800) of 118,958 unique stars in the first year of the Sloan Digital Sky Survey III (2008-2009). SEGUE-2 targeted prioritized distant halo tracers (blue horizontal-branch stars, K giants, and M giants) and metal-poor or
Rockosi, Constance M. et al.Fecha de publicación:
42022 -
Accurate Metallicities for Very Metal-poor Stars from the Ca II Infrared Triplet
The Ca II H and K lines are among the few features available to infer the metallicity of extremely metal-poor stars from medium-resolution spectroscopy. Unfortunately, these lines can overlap with absorption produced in the intervening interstellar medium, introducing systematic errors in the derived metallicities. The strength of the Ca II
Martinez Osorio, Yeisson et al.Fecha de publicación:
42022 -
Strong CO absorption features in massive ETGs
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52022 -
The Seventeenth Data Release of the Sloan Digital Sky Surveys: Complete Release of MaNGA, MaStar, and APOGEE-2 Data
This paper documents the seventeenth data release (DR17) from the Sloan Digital Sky Surveys; the fifth and final release from the fourth phase (SDSS-IV). DR17 contains the complete release of the Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey, which reached its goal of surveying over 10,000 nearby galaxies. The complete release
Abdurro'uf et al.Fecha de publicación:
42022 -
Recurrent Strong Outbursts of an EXor-like Young Eruptive Star Gaia20eae
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32022 -
Detailed Chemical Abundances for a Benchmark Sample of M Dwarfs from the APOGEE Survey
Individual chemical abundances for 14 elements (C, O, Na, Mg, Al, Si, K, Ca, Ti, V, Cr, Mn, Fe, and Ni) are derived for a sample of M dwarfs using high-resolution, near-infrared H-band spectra from the Sloan Digital Sky Survey-IV/Apache Point Observatory Galactic Evolution Experiment (APOGEE) survey. The quantitative analysis included synthetic
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Fundamental physics with ESPRESSO: Precise limit on variations in the fine-structure constant towards the bright quasar HE 0515−4414
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Espectrógrafo de alta resolución en operación en el Gran Telescopio Canarias (GTC) de 10m. usando componentes del espectrógrafo UES, utilizado en el Telescopio William Herschel (WHT) de 4.2 m. entre los años 1992 y 2001.

El Gobierno español concede la Acreditación como Centro de Excelencia Severo Ochoa con el fin de reconocer, premiar y promover la investigación científica de alto nivel en los centros y unidades españoles que tengan un alto nivel de excelencia en el ámbito internacional. Los objetivos específicos del Programa Severo Ochoa son: - Mejorar la