A5091342081- Stellar, planetary, and galactic studies
- Astrophysics and Star Formation Studies
- Astronomy and Astrophysical Research
- Astronomical and nuclear sciences
- Astronomical Observations and Instrumentation
- Gamma-ray bursts and supernovae
- Astro and Planetary Science
- Galaxies: Formation, Evolution, Phenomena
- Astrophysical Phenomena and Observations
- Radioactive element chemistry and processing
- Wildlife-Road Interactions and Conservation
- Nuclear materials and radiation effects
- Environmental and Cultural Studies in Latin America and Beyond
- Bauxite Residue and Utilization
- Mediterranean and Iberian flora and fauna
- Adaptive optics and wavefront sensing
- History and Developments in Astronomy
- Molecular spectroscopy and chirality
University of Concepción
2013-2022
University of La Serena
2021-2022
Universidade Cidade de São Paulo
2022
Universidade de São Paulo
2022
Astronomical Observatory of Rome
2020
European Southern Observatory
2017
The Gaia-ESO Survey is obtaining high-quality spectroscopic data for about 10^5 stars using FLAMES at the VLT. UVES high-resolution spectra are being collected 5000 FGK-type stars. These analyzed in parallel by several state-of-the-art methodologies. Our aim to present how these analyses were implemented, discuss their results, and describe a final recommended parameter scale defined. We also precision (method-to-method dispersion) accuracy (biases with respect reference values) of...
All old Galactic globular clusters (GCs) studied in detail to date host at least two generations of stars, where the second is formed from gas polluted by processed material produced massive stars first. This process can happen if initial mass cluster exceeds a threshold above which ejecta are retained and generation formed. A determination this mandatory order understand how GCs form. We analyzed nine red giant branch belonging Ruprecht 106. Targets were observed with UVES@VLT2...
Context. The nature of the metallicity gradient inside solar circle (RGC < 8 kpc) is poorly understood, but studies Cepheids and a small sample open clusters suggest that it steepens in inner disk.
Context. Open clusters are key tools to study the spatialdistribution of abundances in disk and their evolution with time.
Trumpler 20 is an old open cluster (OC) located toward the Galactic centre, at about 3 kpc from Sun and $\sim$7 centre. Its position makes this particularly interesting in framework of chemical properties disc because very few OCs reside inner part disc. For reason it has been selected as a target Gaia-ESO Survey, spectra many stars main sequence red clump phases are now available. Moreover, although studied by several authors past, no consensus on evolutionary status Tr reached. The heavy...
NGC 3201 is a globular cluster (GC) which shows very peculiar kinematic characteristics including an extreme radial velocity and highly retrograde orbit, strongly suggesting extragalactic origin. Our aims are to study in the context of multiple populations (MPs), hoping constrain possible candidates for self-enrichment by studying chemical abundance pattern, as well adding insight into origin this intriguing cluster. We present detailed analysis eight red giant branch stars using...
Context. Galactic Globular Clusters (GCs) are essential tools to understand the earliest epoch of Milky Way, since they among oldest objects in Universe and can be used trace its formation evolution. Current studies using high resolution spectroscopy for many stars each a large sample GCs allow us develop detailed observational picture about their relation with Galaxy. However, it is necessary complete this by including that belong all major components, Bulge. Aims. Our aim perform chemical...
We present the abundance analysis for a sample of 17 red giant branch stars in metal-poor globular cluster M28 based on high-resolution spectra. This is first extensive spectroscopic study this cluster. derive abundances O, Na, Mg, Al, Si, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Y, Zr, Ba, La, Ce, and Eu. find metallicity [Fe/H] = −1.29 ± 0.01 an α-enhancement +0.34 (errors mean), typical halo clusters regime. A large spread observed light elements Al. Mg also shows anti-correlation with Al...
The Bulge Globular Clusters (GCs) are key tracers of this central ancient component our Galaxy. It is essential to understand their formation and evolution study that the bulge, as well relationship with other Galactic GC systems (halo disk GCs). Our main goals obtain detailed abundances for a sample seven red giant members NGC 6528 in order characterize its chemical composition halo GCs. Moreover, we analyze cluster$'$s behavior associated Multiple Populations (MPs) phenomenon. We obtained...
Context. Bulge globular clusters (BGCs) are exceptional tracers of the formation and chemodynamical evolution this oldest Galactic component. However, until now, observational difficulties have prevented us from taking full advantage these powerful archeological tools. Aims. CAPOS, bulge Cluster APOgee Survey, addresses key topic by observing a large number BGCs, most which only been poorly studied previously. Even their basic parameters, such as metallicity, [{\alpha}/Fe], radial velocity,...
Milky Way open clusters are very diverse in terms of age, chemical composition, and kinematic properties. Intermediate-age old less common, it is even harder to find them inside the solar Galactocentric radius, due high mortality rate strong extinction this region. NGC 6802 one inner disk (IOCs) observed by $Gaia$-ESO survey (GES). This cluster an important target for calibrating abundances derived homogeneity members clusters. Using measurements from internal data release 4 (iDR4), we...
We present the abundance analysis for a sample of 7 red giant branch stars in metal-poor globular cluster NGC 4372 based on UVES spectra acquired as part Gaia-ESO Survey. This is first extensive study this from high resolution spectroscopy. derive abundances O, Na, Mg, Al, Si, Ca, Sc, Ti, Fe, Cr, Ni, Y, Ba, and La. find metallicity [Fe/H] = -2.19 $\pm$ 0.03 no evidence spread. makes one most galactic clusters. also an {\alpha}-enhancement typical halo clusters at metallicity. Significant...
Globular clusters (GCs) are natural laboratories where stellar and chemical evolution can be studied in detail. In addition, their patterns kinematics tell us to which Galactic structure (disc, bulge, halo or extragalactic) the cluster belongs to. NGC 5927 is one of most metal-rich GCs Galaxy its links it thick disc. We present abundance analysis based on high-resolution spectra seven giant stars. The data were obtained using Fibre Large Array Multi Element Spectrograph/Ultraviolet Echelle...
Context: Trumpler 23 is a moderately populated, intermediate-age open cluster within the solar circle at Rgc ~6 kpc. It in crowded field very close to Galactic plane and color-magnitude diagram shows significant contamination possible differential reddening; it relatively understudied for these reasons, but its location makes key object determining abundance distributions. Aims: New data from Gaia-ESO Survey enable first ever radial velocity spectroscopic metallicity measurements this...
We present results from a study of fifteen red giant members the intermediate-metallicity globular cluster (GC) FSR 1758 using high-resolution near-infrared spectra collected with Apache Point Observatory Galactic Evolution Experiment II survey (APOGEE-2), obtained as part CAPOS (the bulge Cluster APOgee Survey). Since its very recent discovery massive GC in region, evoking name Sequoia, this has been an intriguing object highly debated origin, and initially led to suggestion purported...
In this article, we present a detailed chemical analysis of seven red giant members NGC 6553 using high-resolution spectroscopy from VLT FLAMES. We obtained the stellar parameters (Teff, Log(g), vt, [Fe/H]) these stars spectra, and measured abundance for 20 elements, including light iron-peak alpha-elements neutron-capture elements. The metallicities in our sample are consistent with homogeneous distribution. found mean [Fe/H]=-0.14+/-0.07 dex, agreement other studies. Using Mg, Si, Ca Ti...
We present the abundances analysis for a sample of 11 red giant branch stars in metal-poor globular cluster NGC 6809 based on high-resolution spectra. Our main goals are to characterize its chemical composition and analyze this cluster's behavior associated with Multiple Population (MPs) phenomenon. In our work we obtained stellar parameters 24 elements (O, Na, Mg, Al, Si, Ca, Ti, V, Cr, Mn, Fe, Co, Sc, Ni, Cu, Zn, Y, Zr, Ba, La, Ce, Eu, Nd Dy). found radial velocity 174.7 $\pm$ 3.2 km...
More than a decade has passed since the definition of Globular Cluster (GC) changed, and now we know that they host Multiple Populations (MPs). But few GCs do not share behaviour Ruprecht 106 is one these clusters. We analyzed thirteen member red giant branch stars using spectra in wavelength range 6120-6405 Angstroms obtained through GIRAFFE Spectrograph, mounted at UT2 telescope Paranal, as well whole cluster C, V, R I photometry Swope Las Campanas. Atmospheric parameters were determined...
We report the first 3-D kinematical measurements of 88 stars in direction several recently discovered substructures southern periphery Large Magellanic Cloud (LMC) using a combination Gaia proper motions and radial velocities from APOGEE-2 survey. More specifically, we explore lie assorted pointings region LMC where various overdensities have previously been identified maps DECam. By model disk rotation, find that sizeable fraction extreme space are distinct from, not simple extension of,...
It has been proposed that the globular cluster-like system Terzan 5 is surviving remnant of a primordial building block Milky Way bulge, mainly due to age/metallicity spread and distribution its stars in $\alpha$-Fe plane. We employ Sloan Digital Sky Survey (SDSS-IV) data from Apache Point Observatory Galactic Evolution Experiment (APOGEE 2) test this hypothesis. Adopting random sampling technique, we contrast abundances 10 elements with those their bulge field counterparts comparable...
ABSTRACT Globular Clusters (GCs) are now well known to almost universally show multiple populations (MPs). The HST UV Legacy Survey of a large number Galactic GCs in filters optimized explore MPs finds that small fraction GCs, termed Type II, also display more complex, anomalous behaviour. Several well-studied II intrinsic Fe abundance variations, suggesting the other, less well-studied, should exhibit similar Our aim is perform first detailed metallicity analysis NGC 1261, an intermediate...
Globular Clusters are among the oldest objects in Galaxy, thus their researchers key to understanding processes of evolution and formation that galaxy has experienced early stages. Spectroscopic studies allow us carry out detailed analyzes on chemical composition Clusters. The aim our research is perform a analysis abundances sample stars Bulge Cluster NGC 6553, order determine patterns appreciate phenomenon Multiple Population one most metal-rich Galaxy. This being carried with data...
Over the last decade, classical definition of Globular Clusters (GCs) as simple stellar populations was revolutionized due to discovery "Multiple Populations" (MPs). However, our knowledge this phenomenon and its characteristics is still lacking greatly observationally, there currently no scenario that adequately explains origin. It therefore important study many GCs possible characterize whether or not they have MPs, determine their detailed behavior enlighten formation scenarios, using a...