Publications (91)
4MOST Scientific Operations
C. J. Walcher, M. Banerji, C. Battistini +65
The 4MOST instrument is a multi-object spectrograph that will address Galactic and extragalactic science cases simultaneously by observing targets from a large number of different…
Tracing the evolution of NGC6397 through the chemical composition of its stellar populations
K. Lind, C. Charbonnel, T. Decressin +3
With the aim to constrain multiple populations in the metal-poor globular cluster NGC6397, we analyse and discuss the chemical compositions of a large number of elements in 21 red…
The Gaia-ESO Survey: processing of the FLAMES-UVES spectra
G. G. Sacco, L. Morbidelli, E. Franciosini +49
The Gaia-ESO Survey is a large public spectroscopic survey that aims to derive radial velocities and fundamental parameters of about 10^5 Milky Way stars in the field and in cluste…
Non-LTE line formation of Fe in late-type stars IV: Modelling of the solar centre-to-limb variation in 3D
K. Lind, A. M. Amarsi, M. Asplund +7
Our ability to model the shapes and strengths of iron lines in the solar spectrum is a critical test of the accuracy of the solar iron abundance, which sets the absolute zero-point…
The Gaia-ESO Public Spectroscopic Survey: Implementation, data products, open cluster survey, science, and legacy
S. Randich, G. Gilmore, L. Magrini +161
In the last 15 years different ground-based spectroscopic surveys have been started (and completed) with the general aim of delivering stellar parameters and elemental abundances f…
The double sub-giant branch of NGC 6656 (M22): a chemical characterization
A. F. Marino, A. P. Milone, C. Sneden +14
We present an abundance analysis of 101 subgiant branch (SGB) stars in the globular cluster M22. Using low resolution FLAMES/GIRAFFE spectra we have determined abundances of the ne…
The Gaia-ESO Survey: Lithium measurements and new curves of growth
E. Franciosini, S. Randich, P. de Laverny +37
The Gaia-ESO Survey (GES) is a large public spectroscopic survey that was carried out using the multi-object FLAMES spectrograph at the Very Large Telescope. The survey provides ac…
Gaia-ESO Survey: The analysis of pre-main sequence stellar spectra
A. C. Lanzafame, A. Frasca, F. Damiani +70
This paper describes the analysis of UVES and GIRAFFE spectra acquired by the Gaia-ESO Public Spectroscopic Survey in the fields of young clusters whose population includes pre-mai…
Accurate effective temperatures of the metal-poor benchmark stars HD 140283, HD 122563 and HD 103095 from CHARA interferometry
I. Karovicova, T. R. White, T. Nordlander +14
Large stellar surveys of the Milky Way require validation with reference to a set of "benchmark" stars whose fundamental properties are well-determined. For metal-poor benchmark st…
The Gaia-ESO Survey: Abundance ratios in the inner-disk open clusters Trumpler 20, NGC 4815, NGC 6705
L. Magrini, S. Randich, D. Romano +50
Open clusters are key tools to study the spatial distribution of abundances in the disk and their evolution with time. Using the first release of stellar parameters and abundances…
Non-LTE line formation of Fe in late-type stars - III. 3D non-LTE analysis of metal-poor stars
A. M. Amarsi, K. Lind, M. Asplund +2
As one of the most important elements in astronomy, iron abundance determinations need to be as accurate as possible. We investigate the accuracy of spectroscopic iron abundance an…
Observational signatures of lithium depletion in the metal-poor globular cluster NGC6397
K. Lind, F. Primas, C. Charbonnel +2
The "stellar" solution to the cosmological lithium problem proposes that surface depletion of lithium in low-mass, metal-poor stars can reconcile the lower abundances found for Gal…
Gaia-ESO Survey: The analysis of high-resolution UVES spectra of FGK-type stars
R. Smiljanic, A. J. Korn, M. Bergemann +99
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 for about 5000 FGK-t…
The Gaia-ESO Survey: properties of newly discovered Li-rich giants
R. Smiljanic, E. Franciosini, A. Bragaglia +41
We report 20 new lithium-rich giants discovered within the Gaia-ESO Survey, including the first Li-rich giant with evolutionary stage confirmed by CoRoT data. Atmospheric parameter…
The Gaia-ESO Survey: Characterisation of the [alpha/Fe] sequences in the Milky Way discs
G. Kordopatis, R. F. G. Wyse, G. Gilmore +30
We investigate, using the Gaia-ESO Survey internal Data-Release 2, the properties of the double sequence of the Milky Way discs (defined chemically as the high-alpha and low-alpha…
Atomic diffusion and mixing in old stars II. Observations of stars in the globular cluster NGC 6397 with VLT/FLAMES-GIRAFFE
K. Lind, A. J. Korn, P. S. Barklem +1
Evolutionary trends in the surface abundances of heavier elements have recently been identified in the globular cluster NGC 6397 ([Fe/H]=-2), indicating the operation of atomic dif…
The Gaia-ESO Survey: a quiescent Milky Way with no significant dark/stellar accreted disc
G. R. Ruchti, J. I. Read, S. Feltzing +26
According to our current cosmological model, galaxies like the Milky Way are expected to experience many mergers over their lifetimes. The most massive of the merging galaxies will…
Atomic Diffusion and Mixing in Old Stars. III. Analysis of NGC 6397 Stars under New Constraints
T. Nordlander, A. J. Korn, O. Richard +1
We have previously reported on chemical abundance trends with evolutionary state in the globular cluster NGC 6397 discovered in analyses of spectra taken with FLAMES at the VLT. He…
A new algorithm for optimizing the wavelength coverage for spectroscopic studies: Spectral Wavelength Optimization Code (SWOC)
G. R. Ruchti, S. Feltzing, K. Lind +7
The past decade and a half has seen the design and execution of several ground-based spectroscopic surveys, both Galactic and Extra-galactic. Additionally, new surveys are being de…
Iron and s-elements abundance variations in NGC5286: comparison with anomalous globular clusters and Milky Way satellites
A. F. Marino, A. P. Milone, A. I. Karakas +13
We present a high resolution spectroscopic analysis of 62 red giants in the Milky Way globular cluster NGC5286. We have determined abundances of representative light proton-capture…
The Gaia-ESO Survey: Kinematic structure in the Gamma Velorum Cluster
R. D. Jeffries, R. J. Jackson, M. Cottaar +27
Context: A key science goal of the Gaia-ESO survey (GES) is to use the kinematics of low-mass stars in young clusters to probe their dynamical histories and how they populate the f…
Signatures of intrinsic Li depletion and Li-Na anti-correlation in the metal-poor globular cluster NGC6397
K. Lind, F. Primas, C. Charbonnel +2
To alleviate the discrepancy between the prediction of the primordial lithium abundance in the universe and the abundances observed in Pop II dwarfs and subgiant stars, it has been…
R-Process elements from magnetorotational hypernovae
D. Yong, C. Kobayashi, G. S. Da Costa +11
Neutron-star mergers were recently confirmed as sites of rapid-neutron-capture (r-process) nucleosynthesis. However, in Galactic chemical evolution models, neutron-star mergers alo…
Keck HIRES Spectroscopy of SkyMapper Commissioning Survey Candidate Extremely Metal-Poor Stars
A. F. Marino, G. S. Da Costa, A. R. Casey +11
We present results from the analysis of high-resolution spectra obtained with the Keck HIRES spectrograph for a sample of 17 candidate extremely metal-poor (EMP) stars originally s…
Revisiting inelastic Cu+H collisions and the non-LTE Galactic evolution of copper
S. Caliskan, A. M. Amarsi, M. Racca +4
The Galactic evolution of copper remains poorly understood, partly due to the strong departures from local thermodynamic equilibrium (LTE) affecting Cu I lines. A key source of unc…
Titanium abundances in late-type stars, II. Grid of departure coefficients and application to a sample of stars
J. W. E. Mallinson, K. Lind, A. M. Amarsi +1
Rapidly growing datasets from stellar spectroscopic surveys are providing unprecedented opportunities to analyse the chemical evolution history of our Galaxy. However, spectral ana…
Effective temperature determinations of late-type stars based on 3D non-LTE Balmer line formation
A. M. Amarsi, T. Nordlander, P. S. Barklem +3
Hydrogen Balmer lines are commonly used as spectroscopic effective temperature diagnostics of late-type stars. However, the absolute accuracy of classical methods that are based on…
The Gaia-ESO Survey: New constraints on the Galactic disc velocity dispersion and its chemical dependencies
G. Guiglion, A. Recio-Blanco, P. de Laverny +27
Understanding the history and the evolution of the Milky Way disc is one of the main goals of modern astrophysics. We study the velocity dispersion behaviour of Galactic disc stars…
The Gaia-ESO Survey: the most metal-poor stars in the Galactic bulge
L. Howes, M. Asplund, A. R. Casey +39
We present the first results of the EMBLA survey (Extremely Metal-poor BuLge stars with AAOmega), aimed at finding metal-poor stars in the Milky Way bulge, where the oldest stars s…
Raising the observed metallicity floor with a 3D non-LTE analysis of SDSS J102915.14+172927.9
C. Lagae, A. M. Amarsi, L. F. RodrÃguez DÃaz +4
Context: The first stars produced the first heavy elements and set the stage for the formation of the first galaxies. Accurate chemical abundances of ultra metal-poor stars ([Fe/H]…
High resolution spectroscopic follow-up of the most metal-poor candidates from SkyMapper DR1.1
D. Yong, G. S. Da Costa, M. S. Bessell +13
We present chemical abundances for 21 elements (from Li to Eu) in 150 metal-poor Galactic stars spanning 4.1 [Fe/H] 2.1. The targets were selected from the SkyMapper…
The GALAH survey: effective temperature calibration from the InfraRed Flux Method in the Gaia system
L. Casagrande, J. Lin, A. D. Rains +23
In order to accurately determine stellar properties, knowledge of the effective temperature of stars is vital. We implement Gaia and 2MASS photometry in the InfraRed Flux Method an…
The GALAH survey: properties of the Galactic disk(s) in the solar neighbourhood
L. Duong, K. C. Freeman, M. Asplund +26
Using data from the GALAH pilot survey, we determine properties of the Galactic thin and thick disks near the solar neighbourhood. The data cover a small range of Galactocentric ra…
High Precision Differential Abundance Measurements in Globular Clusters: Chemical Inhomogeneities in NGC 6752
David Yong, Jorge Melendez, Frank Grundahl +9
We report on a strictly differential line-by-line analysis of high quality UVES spectra of bright giants in the metal-poor globular cluster NGC 6752. We achieved high precision dif…
3D non-LTE modeling of the stellar center-to-limb variation for transmission spectroscopy studies
G. Canocchi, K. Lind, C. Lagae +5
Context. Transmission spectroscopy is one of the most powerful techniques to characterize transiting exoplanets since it allows to measure the abundance of the atomic and molecular…
The Gaia-ESO Survey: radial metallicity gradients and age-metallicity relation of stars in the Milky Way disk
M. Bergemann, G. Ruchti, A. Serenelli +42
We study the relationship between age, metallicity, and alpha-enhancement of FGK stars in the Galactic disk. The results are based upon the analysis of high-resolution UVES spectra…
The Gaia-ESO Survey: Sodium and aluminium abundances in giants and dwarfs - Implications for stellar and Galactic chemical evolution
R. Smiljanic, D. Romano, A. Bragaglia +40
Stellar evolution models predict that internal mixing should cause some sodium overabundance at the surface of red giants more massive than ~ 1.5--2.0 Msun. The surface aluminium a…
The Gaia-ESO Survey: Exploring the complex nature and origins of the Galactic bulge populations
A. Rojas-Arriagada, A. Recio-Blanco, P. de Laverny +36
Abridged: We used the fourth internal data release of the Gaia-ESO survey to characterize the bulge chemistry, spatial distribution, kinematics, and to compare it chemically with t…
Mg line formation in late-type stellar atmospheres: I. The model atom
Y. Osorio, P. S. Barklem, K. Lind +4
Mg is often traced in late-type stars using lines of neutral magnesium, which is expected to be subject to departures from LTE. The astrophysical importance of Mg as well as its re…
Gaia FGK Benchmark Stars - Metallicity
Paula Jofre, U. Heiter, C. Soubiran +22
To calibrate automatic pipelines that determine atmospheric parameters of stars, one needs a sample of stars -- ``benchmark stars'' -- with well defined parameters to be used as a…
The SkyMapper DR1.1 Search for Extremely Metal-Poor Stars
G. S. Da Costa, M. S. Bessell, A. D. Mackey +10
We present and discuss the results of a search for extremely metal-poor stars based on photometry from data release DR1.1 of the SkyMapper imaging survey of the southern sky. In pa…
3D NLTE spectral line formation of lithium in late-type stars
E. Wang, T. Nordlander, M. Asplund +3
Accurately known stellar lithium abundances may be used to shed light on a variety of astrophysical phenomena such as Big Bang nucleosynthesis, radial migration, ages of stars and…
Fe I Oscillator Strengths for Transitions from High-lying Even-Parity Levels
E. A. Den Hartog, M. P. Ruffoni, J. E. Lawler +3
New radiative lifetimes, measured to 5 % accuracy, are reported for 31 even-parity levels of Fe I ranging from 45061 cm to 56842 cm. These lifetimes have been m…
Carbon and oxygen in metal-poor halo stars
A. M. Amarsi, P. E. Nissen, M. Asplund +2
Carbon and oxygen are key tracers of the Galactic chemical evolution; in particular, a reported upturn in [C/O] towards decreasing [O/H] in metal-poor halo stars could be a signatu…
A single low-energy, iron-poor supernova as the source of metals in the star SMSS J 031300.36-670839.3
S. C. Keller, M. S. Bessell, A. Frebel +11
The element abundance ratios of four low-mass stars with extremely low metallicities indicate that the gas out of which the stars formed was enriched in each case by at most a few,…
The GALAH Survey: Non-LTE departure coefficients for large spectroscopic surveys
A. M. Amarsi, K. Lind, Y. Osorio +23
Massive sets of stellar spectroscopic observations are rapidly becoming available and these can be used to determine the chemical composition and evolution of the Galaxy with unpre…
The GALAH survey: Multiple stars and our Galaxy. I. A comprehensive method for deriving properties of FGK binary stars
G. Traven, S. Feltzing, T. Merle +24
Binary stellar systems form a large fraction of the Galaxy's stars. They are useful as laboratories for studying the physical processes taking place within stars, and must be corre…
The halo+cluster system of the Galactic globular cluster NGC1851
A. F. Marino, A. P. Milone, D. Yong +17
NGC1851 is surrounded by a stellar component that extends more than ten times beyond the tidal radius. Although the nature of this stellar structure is not known, it has been sugge…
Stellar science from a blue wavelength range - A possible design for the blue arm of 4MOST
C. J. Hansen, H. -G. Ludwig, W. Seifert +12
From stellar spectra, a variety of physical properties of stars can be derived. In particular, the chemical composition of stellar atmospheres can be inferred from absorption line…
The Gaia-ESO Survey: the Galactic Thick to Thin Disc transition
A. Recio-Blanco, P. de Laverny, G. Kordopatis +36
(Abridged) We have used the atmospheric parameters, [alpha/Fe] abundances and radial velocities, determined from the Gaia-ESO Survey GIRAFFE spectra of FGK-type stars (iDR1), to pr…
Helium enhanced stars and multiple populations along the horizontal branch of NGC2808: direct spectroscopic measurements
A. F. Marino, A. P. Milone, N. Przybilla +15
We present an abundance analysis of 96 horizontal branch (HB) stars in NGC2808, a globular cluster exhibiting a complex multiple stellar population pattern. These stars are distrib…
The Gaia-ESO Survey: homogenisation of stellar parameters and elemental abundances
A. Hourihane, P. Francois, C. C. Worley +59
The Gaia-ESO Survey is a public spectroscopic survey that has targeted stars covering all major components of the Milky Way from the end of 2011 to 2018, delivering i…
Ca line formation in late-type stellar atmospheres: I. The model atom
Y. Osorio, K. Lind, P. S. Barklem +2
Context. Departures from local thermodynamic equilibrium (LTE) distort the calcium abundance derived from stellar spectra in various ways, depending on the lines used and the stell…
Horizontal-branch morphology and multiple stellar populations in the anomalous globular cluster M22
A. F. Marino, A. P. Milone, K. Lind
M22 is an anomalous globular cluster that hosts two groups of stars with different metallicity and s-element abundance. The star-to-star light-element variations in both groups, wi…
Non-detection of Li in Spite plateau stars with ESPRESSO
E. X. Wang, T. Nordlander, M. Asplund +3
The detection of Li in Spite plateau stars contradicts the standard Big Bang nucleosynthesis prediction, known as the second cosmological lithium problem. We measure the isotop…
The GALAH survey: An abundance, age, and kinematic inventory of the solar neighbourhood made with TGAS
S. Buder, K. Lind, M. K. Ness +31
The overlap between the spectroscopic Galactic Archaeology with HERMES (GALAH) survey & provides a high-dimensional chemodynamical space of unprecedented size. We present a…
The Gaia-ESO Public Spectroscopic Survey: Motivation, implementation, GIRAFFE data processing, analysis, and final data products
G. Gilmore, S. Randich, C. C. Worley +165
The Gaia-ESO Public Spectroscopic Survey is an ambitious project designed to obtain astrophysical parameters and elemental abundances for 100,000 stars, including large representat…
The Gaia-ESO Survey: the present-day radial metallicity distribution of the Galactic disc probed by pre-main-sequence clusters
L. Spina, S. Randich, L. Magrini +35
The radial metallicity distribution in the Galactic thin disc represents a crucial constraint for modelling disc formation and evolution. Open clusters allow us to derive both the…
Probing Na in giant exoplanets with ESPRESSO and 3D NLTE stellar spectra
G. Canocchi, G. Morello, K. Lind +3
Neutral sodium was the first atom detected in an exoplanetary atmosphere via transmission spectroscopy and remains the most frequently detected species due to its strong doublet in…
The lowest detected stellar Fe abundance: The halo star SMSS J160540.18-144323.1
T. Nordlander, M. S. Bessell, G. S. Da Costa +12
We report the discovery of SMSS J160540.18-144323.1, a new ultra-metal poor halo star discovered with the SkyMapper telescope. We measure [Fe/H] = -6.2 +- 0.2 (1D LTE), the lowest…
4MOST Consortium Survey 2: The Milky Way Halo High-Resolution Survey
N. Christlieb, C. Battistini, P. Bonifacio +19
We will study the formation history of the Milky Way, and the earliest phases of its chemical enrichment, with a sample of more than 1.5 million stars at high galactic latitude. El…
Departures from LTE for neutral Li in late-type stars
K. Lind, M. Asplund, P. S. Barklem
We perform non-LTE calculations of lithium in late-type stars for a wide range of stellar parameters, including quantum mechanical cross-sections for collisions with neutral hydrog…
The Gaia-ESO Survey: Empirical determination of the precision of stellar radial velocities and projected rotation velocities
R. J. Jackson, R. D. Jeffries, J. Lewis +58
The Gaia-ESO Survey (GES) is a large public spectroscopic survey at the European Southern Observatory Very Large Telescope. A key aim is to provide precise radial velocities (RVs)…
The influence of electron collisions on non-LTE Li line formation in stellar atmospheres
Y. Osorio, P. S. Barklem, K. Lind +1
The influence of the uncertainties in the rate coefficient data for electron-impact excitation and ionization on non-LTE Li line formation in cool stellar atmospheres is investigat…
Titanium abundances in late-type stars I. 1D non-local thermodynamic equilibrium modelling in benchmark dwarfs and giants
J. W. E. Mallinson, K. Lind, A. M. Amarsi +4
The titanium abundances of late-type stars are important tracers of Galactic formation history. However, abundances inferred from Ti I and Ti II lines can be in stark disagreement…
4MOST Consortium Survey 4: Milky Way Disc and Bulge High-Resolution Survey (4MIDABLE-HR)
T. Bensby, M. Bergemann, J. Rybizki +21
The signatures of the formation and evolution of a galaxy are imprinted in its stars. Their velocities, ages, and chemical compositions present major constraints on models of galax…
The Gaia-ESO Survey: Separating disk chemical substructures with cluster models
A. Rojas-Arriagada, A. Recio-Blanco, P. de Laverny +24
(Abridged) Recent spectroscopic surveys have begun to explore the Galactic disk system outside the solar neighborhood on the basis of large data samples. In this way, they provide…
Empirical classification of VLT/Giraffe stellar spectra in the wavelength range 6440-6810 A in the gamma Vel cluster, and calibration of spectral indices
F. Damiani, L. Prisinzano, G. Micela +23
We study spectral diagnostics available from optical spectra with R=17000 obtained with the VLT/Giraffe HR15n setup, using observations from the Gaia-ESO Survey, on the gamma Vel y…
The Gaia-ESO Survey: Properties of the intermediate age open cluster NGC 4815
E. D. Friel, P. Donati, A. Bragaglia +34
NGC 4815 is a populous ~500 Myr open cluster at a Galactocentric radius of 7 kpc observed in the first six months of the Gaia-ESO Survey. Located in the inner Galactic disk, NGC 48…
Extremely metal-poor stars from the cosmic dawn in the bulge of the Milky Way
L. M. Howes, A. R. Casey, M. Asplund +22
The first stars are predicted to have formed within 200 million years after the Big Bang, initiating the cosmic dawn. A true first star has not yet been discovered, although stars…
The GALAH Survey: Data Release 4
S. Buder, J. Kos, E. X. Wang +36
The stars of the Milky Way carry the chemical history of our Galaxy in their atmospheres as they journey through its vast expanse. Like barcodes, we can extract the chemical finger…
The Gaia-ESO Survey: The DR5 analysis of the medium-resolution GIRAFFE and high-resolution UVES spectra of FGK-type stars
C. C. Worley, R. Smiljanic, L. Magrini +42
The Gaia-ESO Survey is an European Southern Observatory (ESO) public spectroscopic survey that targeted stars in the Milky Way covering the major populations of the disk, bu…
Fe I Oscillator Strengths for the Gaia-ESO Survey
M. P. Ruffoni, E. A. Den Hartog, J. E. Lawler +4
The Gaia-ESO Public Spectroscopic Survey (GES) is conducting a large-scale study of multi-element chemical abundances of some 100 000 stars in the Milky Way with the ultimate aim o…
Non-LTE abundance corrections for late-type stars from 2000à to 3μm: I. Na, Mg, and Al
K. Lind, T. Nordlander, A. Wehrhahn +6
It is well known that cool star atmospheres depart from local thermodynamic equilibrium (LTE). Accurate abundance determination requires taking those effects into account, but the…
The Gaia-ESO Survey: Churning through the Milky Way
M. R. Hayden, A. Recio-Blanco, P. de Laverny +29
We attempt to determine the relative fraction of stars that have undergone significant radial migration by studying the orbital properties of metal-rich ([Fe/H]) stars within…
The Gaia -ESO Survey: Lithium enrichment histories of the Galactic thick and thin disc
Xiaoting. Fu, D. Romano, A. Bragaglia +32
Lithium abundance in most of the warm metal-poor main sequence stars shows a constant plateau (A(Li)~2.2 dex) and then the upper envelope of the lithium vs. metallicity distributio…
Sodium-Oxygen anticorrelation among Horizontal Branch Stars in the Globular Cluster M4
A. F Marino, S. Villanova, A. P. Milone +4
The horizontal branch (HB) morphology of globular clusters (GC) is mainly governed by metallicity. The second parameter problem, well known since the 60's, states that metallicity…
Chemical abundances in the multiple sub-giant branch of 47 Tucanae: insights on its faint sub-giant branch component
A. F. Marino, A. P. Milone, L. Casagrande +8
The globular cluster 47 Tuc exhibits a complex sub-giant branch (SGB) with a faint-SGB comprising only about the 10% of the cluster mass and a bright-SGB hosting at least two disti…
Sun-like stars unlike the Sun: Clues for chemical anomalies of cool stars
V. Adibekyan, E. Delgado-Mena, S. Feltzing +11
We present a summary of the splinter session "Sun-like stars unlike the Sun" that was held on 09 June 2016 as part of the Cool Stars 19 conference (Uppsala, Sweden). We discussed t…
The GALAH Survey: Scientific Motivation
G. M. De Silva, K. C. Freeman, J. Bland-Hawthorn +44
The GALAH survey is a large high-resolution spectroscopic survey using the newly commissioned HERMES spectrograph on the Anglo-Australian Telescope. The HERMES spectrograph provide…
The Gaia-ESO survey: Metal-rich bananas in the bulge
Angus A. Williams, N. W. Evans, Matthew Molloy +25
We analyse the kinematics of giant stars in the direction of the Galactic bulge, extracted from the Gaia-ESO survey in the region $-10^\circ \lesssim \ell \lesssim 10^\…
Atomic and Molecular Data for Optical Stellar Spectroscopy
U. Heiter, K. Lind, M. Asplund +7
High-precision spectroscopy of large stellar samples plays a crucial role for several topical issues in astrophysics. Examples include studying the chemical structure and evolution…
The Gaia-ESO Survey: Revisiting the Li-rich giant problem
A. R. Casey, G. Ruchti, T. Masseron +48
The discovery of lithium-rich giants contradicts expectations from canonical stellar evolution. Here we report on the serendipitous discovery of 20 Li-rich giants observed during t…
3D NLTE Sodium abundances in late-type stars. Abundance corrections and synthetic spectra
G. Canocchi, E. X. Wang, A. M. Amarsi +2
Neutral sodium is an important tracer of the Galactic chemical evolution, a powerful diagnostic of different stellar populations, and the subject of detailed studies of exoplanet a…
The Gaia-ESO Survey: A globular cluster escapee in the Galactic halo
K. Lind, S. E. Koposov, C. Battistini +37
A small fraction of the halo field is made up of stars that share the light element (Z<=13) anomalies characteristic of second generation globular cluster (GC) stars. The ejected s…
Gaia FGK benchmark stars: abundances of alpha and iron-peak elements
P. Jofré, U. Heiter, C. Soubiran +26
In the current era of large spectroscopic surveys of the Milky Way, reference stars for calibrating astrophysical parameters and chemical abundances are of paramount importance. We…
Exploring the Galaxy's halo and very metal-weak thick disk with SkyMapper and Gaia DR2
G. Cordoni, G. S. Da Costa, D. Yong +16
In this work we combine spectroscopic information from the \textit{SkyMapper survey for Extremely Metal-Poor stars} and astrometry from Gaia DR2 to investigate the kinematics of a…
The Gaia-ESO Survey: Spectroscopic-asteroseismic analysis of K2 stars in Gaia-ESO
C. C. Worley, P. Jofre, B. Rendle +33
The extensive stellar spectroscopic datasets that are available for studies in Galactic Archeaology thanks to, for example, the Gaia-ESO Survey, now benefit from having a significa…
4MOST: Project overview and information for the First Call for Proposals
R. S. de Jong, O. Agertz, A. Agudo Berbel +335
We introduce the 4-metre Multi-Object Spectroscopic Telescope (4MOST), a new high-multiplex, wide-field spectroscopic survey facility under development for the four-metre-class Vis…
The GALAH Survey: Second Data Release
S. Buder, M. Asplund, L. Duong +39
The Galactic Archaeology with HERMES (GALAH) survey is a large-scale stellar spectroscopic survey of the Milky Way and designed to deliver chemical information complementary to a l…
Non-LTE calculations for neutral Na in late-type stars using improved atomic data
K. Lind, M. Asplund, P. S. Barklem +1
Neutral sodium is a minority species in the atmospheres of late-type stars, and line formation in local thermodynamic equilibrium (LTE) is often a poor assumption, in particular fo…