Publications (88)
Stroemgren photometry of Galactic Globular Clusters. I. New Calibrations of the metallicity index
A. Calamida, G. Bono, P. B. Stetson +15
We present a new calibration of the Stroemgren metallicity index m1 using red giant (RG) stars in 4 globular clusters (GCs:M92,M13,NGC1851,47Tuc) with metallicity ranging from [Fe/…
The Metallicity Dependence of the Cepheid Period-Luminosity Relation
M. Romaniello, M. Mottini, F. Primas +3
We have assessed the influence of the stellar iron content on the Cepheid Period-Luminosity (PL) relation by relating the V band residuals from the Freedman et al (2001) PL relatio…
First Stars VIII -- Enrichment of the neutron-capture elements in the early Galaxy
P. Francois, E. Depagne, V. Hill +12
Our aim is to measure accurate, homogeneous neutron-capture element abundances for the sample of 32 EMP giant stars studied earlier in this series, including 22 stars with [Fe/H] $…
The beryllium abundance in the very metal-poor halo star G 64-12 from VLT/UVES observations
F. Primas, M. Asplund, P. E. Nissen +1
We report on a new spectroscopic analysis of the very metal deficient star G 64-12 ([Fe/H]=-3.3), aimed at determining, for the first time, its Be content. The spectra were observe…
Tracing mixing in stars: new beryllium observations of the open clusters NGC 2516, Hyades, and M67
S. Randich, F. Primas, L. Pasquini +2
Determinations of beryllium abundance in stars, together with lithium, provide a key tool to investigate the so far poorly understood extra-mixing processes at work in stellar inte…
On the relative distance of Magellanic Clouds using Cepheid NlR and Optical-NIR PW relations
L. Inno, G. Bono, N. Matsunaga +8
We present new estimates of the relative distance of the Magellanic Clouds (MCs) by using NIR and Optical-NIR Cepheid Period Wesenheit (PW) relations. The relative distances are in…
On the fine structure of the Cepheid metallicity gradient in the Galactic thin disk
K. Genovali, B. Lemasle, G. Bono +15
We present homogeneous and accurate iron abundances for 42 Galactic Cepheids based on high-spectral resolution (R~38,000) high signal-to-noise ratio (SNR>100) optical spectra colle…
Homogeneity in the early chemical evolution of the Sextans dwarf Spheroidal galaxy
R. Lucchesi, C. Lardo, F. Primas +10
We present the high-resolution spectroscopic analysis of two new extremely metal-poor stars (EMPS) candidates in the dwarf spheroidal galaxy Sextans. These targets were pre-selecte…
Detailed chemical composition of Galactic Cepheids. A determination of the Galactic abundance gradient in the 8-12 kpc region
B. Lemasle, P. Francois, G. Bono +3
The recent introduction of high resolution/large spectral range spectrographs provided the opportunity to investigate in detail the chemical composition of classical Cepheids. This…
The influence of chemical composition on the properties of Cepheid stars I - Period-Luminosity relation vs iron abundance
M. Romaniello, F. Primas, M. Mottini +3
We have assessed the influence of the stellar iron content on the Cepheid Period-Luminosity (PL) relation by relating the V band residuals from the Freedman et al (2001) PL relatio…
The early days of the Sculptor dwarf spheroidal galaxy
P. Jablonka, P. North, L. Mashonkina +11
We present the high resolution spectroscopic study of five -3.9<=[Fe/H]<=-2.5 stars in the Local Group dwarf spheroidal, Sculptor, thereby doubling the number of stars with compara…
The Carina Project. VIII. The α-element abundances
M. Fabrizio, M. Nonino, G. Bono +16
We have performed a new abundance analysis of Carina Red Giant (RG) stars from spectroscopic data collected with UVES (high resolution) and FLAMES/GIRAFFE (high and medium resoluti…
Galactic abundance gradients from Cepheids : On the iron abundance gradient around 10-12 kpc
B. Lemasle, P. Francois, A. Piersimoni +5
Context: Classical Cepheids can be adopted to trace the chemical evolution of the Galactic disk since their distances can be estimated with very high accuracy. Aims: Homogeneous ir…
Li and Be depletion in metal-poor subgiants
A. E. GarcÃa Pérez, F. Primas
A sample of metal-poor subgiants has been observed with the UVES spectrograph at the Very Large Telescope and abundances of Li and Be have been determined. Typical signal-to-noise…
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 Dependency of the Cepheid Period-Luminosity Relation on Chemical Composition
M. Romaniello, F. Primas, M. Mottini +6
The dependency of the Cepheid Period-Luminosity Relation on chemical composition at different wavelengths is assessed via direct detailed abundance analysis of Galactic and Magella…
First stars VI - Abundances of C, N, O, Li, and mixing in extremely metal-poor giants. Galactic evolution of the light elements
M. Spite, R. Cayrel, B. Plez +11
We have investigated the poorly-understood origin of nitrogen in the early Galaxy by determining N abundances in 35 extremely metal-poor halo giants (22 stars have [Fe/H]<-3.0) usi…
Manganese in dwarf spheroidal galaxies
P. North, G. Cescutti, P. Jablonka +10
We provide manganese abundances (corrected for the effect of the hyperfine structure) for a large number of stars in the dwarf spheroidal galaxies Sculptor and Fornax, and for a sm…
The metallicity dependence of the Cepheid PL-relation
M. A. T. Groenewegen, M. Romaniello, F. Primas +1
A sample of 37 Galactic, 10 LMC and 6 SMC cepheids is compiled for which individual metallicity estimates exist and BVIK photometry in almost all cases. The Galactic cepheids all h…
Measurement of stellar age from uranium decay
R. Cayrel, V. Hill, T. Beers +10
The ages of the oldest stars in the Galaxy indicate when star formation began, and provide a minimum age for the Universe. Radioactive dating of meteoritic material and stars relie…
Metallicity estimates of Galactic Cepheids based on Walraven photometry
S. Pedicelli, J. Lub, J. W. Pel +13
We present new empirical and theoretical calibrations of two photometric metallicity indices based on Walraven photometry. The empirical calibration relies on a sample of 48 Cephei…
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…
A study of the metal-rich, thick disk globular cluster NGC5927
J. Simmerer, S. Feltzing, F. Primas
We present a list of 72 radial velocity member stars in the metal-rich globular cluster NGC5927. The radial velocities are based on multi-epoch, multi-fibre spectra. We identify 46…
First Stars XI. Chemical composition of the extremely metal-poor dwarfs in the binary CS 22876--032
J. I. González Hernández, P. Bonifacio, H. -G. Ludwig +15
We have used high-resolution, high-S/N ratio spectra from the UVES spectrograph at the ESO VLT telescope. Long-term radial-velocity measurements and broad-band photometry allow us…
Detailed chemical composition of classical Cepheids in the LMC cluster NGC 1866 and in the field of the SMC
B. Lemasle, M. A. T. Groenewegen, E. K. Grebel +11
Context: Cepheids are excellent tracers of young stellar populations. They play a crucial role in astrophysics as standard candles. The chemistry of classical Cepheids in the Milky…
First stars IV.CS 29497-030: Evidence for operation of the s-process at very low metallicity
T. Sivarani, P. Bonifacio, P. Molaro +12
We present an abundance analysis of the very metal-poor, carbon-enhanced star CS 29497-030. Our results indicate that this unusually hot turnoff star (Teff = 6650K, log g = 3.5) ha…
New NIR light-curve templates for classical Cepheids
L. Inno, N. Matsunaga, M. Romaniello +22
We present new near-infrared (NIR) light-curve templates for fundamental (FU, JHK) and first overtone (FO, J) Cepheids. The new templates together with PL and PW relations provide…
Extremely metal-poor stars in classical dwarf spheroidal galaxies: Fornax, Sculptor and Sextans
M. Tafelmeyer, P. Jablonka, V. Hill +13
We present the results of a dedicated search for extremely metal-poor stars in the Fornax, Sculptor and Sextans dSphs. Five stars were selected from two earlier VLT/Giraffe and HET…
First stars IX -Mixing in extremely metal-poor giants. Variation of the 12C/13C, [Na/Mg] and [Al/Mg] ratios
M. Spite, R. Cayrel, V. Hill +11
Extremely metal-poor (EMP) stars preserve a fossil record of the composition of the ISM when the Galaxy formed. It is crucial, however, to verify whether internal mixing has modifi…
First stars V - Abundance patterns from C to Zn and supernova yields in the early Galaxy
R. Cayrel, E. Depagne, M. Spite +11
In the framework of an ESO Large Programme high quality spectra of 70 very metal-poor dwarfs and giants were obtained with the VLT-UVES combination. This paper reports the detailed…
First stars XII. Abundances in extremely metal-poor turnoff stars,and comparison with the giants
P. Bonifacio, M. Spite, R. Cayrel +13
CONTEXT:The detailed chemical abundances of extremely metal-poor (EMP) stars are key guides to understanding the early chemical evolution of the Galaxy. Most existing data are, how…
Stellar abundances and ages for metal-rich Milky Way globular clusters - Stellar parameters and elemental abundances for 9 HB stars in NGC6352
S. Feltzing, F. Primas, R. A. Johnson
[ABRIDGED] Metal-rich globular clusters provide important tracers of the formation of our Galaxy. Moreover, and not less important, they are very important calibrators for the deri…
O/Fe in metal-poor main sequence and subgiant stars
P. E. Nissen, F. Primas, M. Asplund +1
A study of the O/Fe ratio in metal-poor main sequence and subgiant stars is presented using the [OI] 6300A line, the OI 7774A triplet, and a selection of weak FeII lines observed o…
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…
A VLT-UVES spectrscopic analysis of C-rich Fe-poor stars
T. Masseron, B. Plez, F. Primas +2
Large surveys of very metal-poor stars have revealed in recent years that a large fraction of these objects were carbon-rich, analogous to the more metal-rich CH-stars. The abundan…
On the metallicity distribution of classical Cepheids in the Galactic inner disk
K. Genovali, B. Lemasle, G. Bono +10
We present homogeneous and accurate iron abundances for almost four dozen (47) of Galactic Cepheids using high-spectral resolution (R40,000) high signal-to-noise ratio (S/N $…
New Baade-Wesselink distances and radii for four metal-rich Galactic Cepheids
S. Pedicelli, B. Lemasle, M. Groenewegen +10
We provided accurate estimates of distances, radii and iron abundances for four metal-rich Cepheids, namely V340 Ara, UZ Sct, AV Sgr and VY Sgr. The main aim of this investigation…
Element abundances of unevolved stars in the open cluster M 67
S. Randich, P. Sestito, F. Primas +2
We determined the metallicity ([Fe/H]), together with O, Na, Mg, Al, Si, Ca, Ti, Cr and Ni abundances for a sample of 10 unevolved or slightly evolved stars belonging to the open c…
The Lithium Content of the Galactic Halo Stars
C. Charbonnel, F. Primas
Thanks to the accurate determination of the baryon density of the universe by the recent cosmic microwave background experiments, updated predictions of the standard model of Big B…
The Chemical Composition of Cepheids in the Milky Way and the Magellanic Clouds
M. Mottini, M. Romaniello, F. Primas +3
We have measured the elemental abundances of 68 Galactic and Magellanic Cepheids from FEROS and UVES high-resolution and high signal-to-noise spectra in order to establish the infl…
Extremely metal-poor stars in the Fornax and Carina dwarf spheroidal galaxies
R. Lucchesi, P. Jablonka, Ã. Skúladóttir +6
We present our analysis of VLT/UVES and X-shooter observations of six very metal-poor stars, including four stars at [Fe/H] in the Fornax and Carina dwarf spheroidal (…
Chemical abundances in LMC stellar populations. II. The bar sample
M. Van der Swaelmen, V. Hill, F. Primas +1
This paper compares the chemical evolution of the Large Magellanic Cloud (LMC) to that of the Milky Way (MW) and investigates the relation between the bar and the inner disc of the…
A holistic approach to carbon-enhanced metal-poor stars
T. Masseron, J. A. Johnson, B. Plez +4
By considering the various CEMP subclasses separately, we try to derive, from the specific signatures imprinted on the abundances, parameters (such as metallicity, mass, temperatur…
Elemental abundances of metal poor carbon rich lead star: CS29497-030
T. Sivarani, P. Bonifacio, P. Molaro +12
We present here the abundance analysis of a metal poor carbon rich lead star, CS29497-030. High resolution and high signal to noise spectra were obtained using the UVES spectrograp…
A high resolution VLT/FLAMES study of individual stars in the centre of the Fornax dwarf spheroidal galaxy
B. Letarte, V. Hill, E. Tolstoy +13
For the first time we show the detailed late-stage chemical evolution history of small nearby dwarf spheroidal galaxy in the Local Group. We present the results of a high resolutio…
Chemical Composition of Extremely Metal-Poor Stars in the Sextans Dwarf Spheroidal Galaxy
W. Aoki, N. Arimoto, K. Sadakane +15
Chemical abundances of six extremely metal-poor ([Fe/H]<-2.5) stars in the Sextans dwarf spheroidal galaxy are determined based on high resolution spectroscopy (R=40,000) with the…
A new view of the dwarf spheroidal satellites of the Milky Way from VLT/FLAMES: Where are the very metal poor stars?
Amina Helmi, M. J. Irwin, E. Tolstoy +13
As part of the Dwarf galaxies Abundances and Radial-velocities Team (DART) program, we have measured the metallicities of a large sample of stars in four nearby dwarf spheroidal ga…
Cepheids as tracers of the metallicity gradient across the Galactic disk
B. Lemasle, A. Piersimoni, S. Pedicelli +4
We present iron abundance measurements, based on high resolution spectroscopy, and accurate distance determinations, based on near infrared photometry, for 34 Galactic Cepheids. Th…
The ESO Large Programme First Stars
P. Bonifacio, J. Andersen, S. Andrievsky +19
In ESO period 65 (April-September 2000) the large programme 165.N-0276, led by Roger Cayrel, began making use of UVES at the Kueyen VLT telescope. Known within the Team and outside…
Possible signature of hypernova nucleosynthesis in a beryllium rich halo dwarf
R. Smiljanic, L. Pasquini, F. Primas +3
As part of a large survey of halo and thick disc stars, we found one halo star, HD 106038, exceptionally overabundant in beryllium. In spite of its low metallicity, [Fe/H] = -1.26,…
First stars VII. Lithium in extremely metal poor dwarfs
P. Bonifacio, P. Molaro, T. Sivarani +12
Aims. This study aims to determine the level and constancy of the Spite plateau as definitively as possible from homogeneous high-quality VLT-UVES spectra of 19 of the most metal-p…
Chemical abundances in LMC stellar populations I. The Inner disk sample Based on observations collected at the VLT UT2 telescope
L. Pompeia, V. Hill, M. Spite +6
The advent of the new class 8 meters telescopes allows for the first time the detailed study of numerous stars of galaxies other than our own. The Large Magellanic Cloud is one of…
Stromgren photometry of Galactic Globular Clusters. II Metallicity distribution of red giants in Omega Centauri
A. Calamida, G. Bono, P. B. Stetson +23
We present new intermediate-band Stroemgren photometry based on more than 300 u,v,b,y images of the Galactic globular cluster Omega Cen. Optical data were supplemented with new mul…
First stars X. The nature of three unevolved Carbon-Enhanced Metal-Poor stars
T. Sivarani, T. C. Beers, P. Bonifacio +13
From high-resolution VLT/UVES spectra (R~43,000), we determine abundances or upper limits for Li, C, N, O, and other important elements, as well as 12C/13C isotopic ratio for three…
First Stars II. Elemental abundances in the extremely metal-poor star CS 22949--037: A diagnostic of early massive supernovae
E. Depagne, V. Hill, M. Spite +10
CS 22949--037 is one of the most metal-poor giants known ([Fe/H]), and it exhibits large overabundances of carbon and nitrogen (Norris et al.). Using VLT-UVES spectra…
Sodium abundances of AGB and RGB stars in Galactic globular clusters II. Analysis and results of NGC 104, NGC 6121 and NGC 6809
Y. Wang, F. Primas, C. Charbonnel +4
We analyzed the high-resolution spectra of a large sample of AGB and RGB stars in the Galactic globular clusters (GCs) NGC 104, NGC 6121, and NGC 6809 obtained with FLAMES/GIRAFFE…
VLT/FLAMES spectroscopy of red giant branch stars in the Fornax dwarf spheroidal galaxy
B. Lemasle, T. de Boer, V. Hill +13
Fornax is one of the most massive dwarf spheroidal galaxies in the Local Group. The Fornax field star population is dominated by intermediate age stars but star formation was going…
Lithium Abundance of Halo Dwarfs Revised
P. Molaro, F. Primas, P. Bonifacio
Lithium abundances in a sample of halo dwarfs have been redetermined by using the new T derived by Fuhrmann et al (1994) from modelling of the Balmer lines. These T…
The DART imaging and CaT survey of the Fornax Dwarf Spheroidal Galaxy
G. Battaglia, E. Tolstoy, A. Helmi +13
As part of the DART project we have used the ESO/2.2m Wide Field Imager in conjunction with the VLT/FLAMES GIRAFFE spectrograph to study the detailed properties of the resolved ste…
Lead abundance in the uranium star CS 31082-001
B. Plez, V. Hill, R. Cayrel +6
In a previous paper we were able to measure the abundance of uranium and thorium in the very-metal poor halo giant BPS CS 31082-001, but only obtained an upper limit for the abunda…
Boron in the very metal-poor star BD-13 3442
D. K. Duncan, L. M. Rebull, F. Primas +5
The Goddard High Resolution Spectrograph (GHRS) of the Hubble Space Telescope (HST) has been used to observe the boron 2500 A region of BD-13 3442. At a metallicity of [Fe/H]=-3.00…
Classical Cepheids, what else?
G. Bono, L. Inno, N. Matsunaga +4
We present new and independent estimates of the distances to the Magellanic Clouds (MCs) using near-infrared (NIR) and optical--NIR period--Wesenheit (PW) relations. The slopes of…
The Extremely Metal-Poor, Neutron-Capture-Rich Star CS 22892-052: A Comprehensive Abundance Analysis
C. Sneden, J. J. Cowan, J. E. Lawler +9
High-resolution spectra obtained with three ground-based facilities and the Hubble Space Telescope (HST) have been combined to produce a new abundance analysis of CS 22892-052, an…
VLT/UVES Abundances in Four Nearby Dwarf Spheroidal Galaxies: II. Implications for Understanding Galaxy Evolution
Eline Tolstoy, K. A. Venn, M. Shetrone +4
We have used UVES on VLT-UT2 to take spectra of 15 individual red giant stars in the centers of four nearby dwarf spheroidal galaxies: Sculptor, Fornax, Carina and Leo I. We measur…
The Carina Project. V. The impact of NLTE effects on the iron content
M. Fabrizio, T. Merle, F. Thévenin +21
We have performed accurate iron abundance measurements for 44 red giants (RGs) in the Carina dwarf spheroidal (dSph) galaxy. We used archival, high-resolution spectra (R~38,000) co…
Scientific Text Analysis with Robots applied to observatory proposals
T. Jerabkova, H. M. J. Boffin, F. Patat +3
To test the potential disruptive effect of Artificial Intelligence (AI) transformers (e.g., ChatGPT) and their associated Large Language Models on the time allocation process, both…
VLT/UVES Abundances in Four Nearby Dwarf Spheroidal Galaxies: I. Nucleosynthesis and Abundance Ratios
M. Shetrone, K. A. Venn, E. Tolstoy +3
We have used UVES on VLT-UT2 to take spectra of 15 red giants in the Sculptor, Fornax, Carina and Leo I dwarf spheroidal galaxies. We measure the abundances of alpha, iron peak, s…
Galactic abundance gradients from Cepheids: alpha and heavy elements in the outer disk
B. Lemasle, P. Francois, K. Genovali +11
Context: Galactic abundance gradients set strong constraints to chemo-dynamical evolutionary models of the Milky Way. Given the PL relations that provide accurate distances and the…
CS 30322-023: an ultra metal-poor TP-AGB star?
T. Masseron, S. Van Eck, B. Famaey +6
With [Fe/H] = -3.5, CS 30322-023 is the most metal-poor star to exhibit a clear s-process signature and the most metal-poor ``lead star'' known. CS 30322-023 is also remarkable in…
First Stars XIV. Sulfur abundances in extremely metal-poor (EMP) stars
Monique Spite, E. Caffau, S. M. Andrievsky +15
Sulfur is important: the site of its formation is uncertain, and at very low metallicity the trend of [S/Fe] against [Fe/H] is controversial. Below [Fe/H]=-2.0, [S/Fe] remains cons…
On the metallicity gradient of the Galactic disk
S. Pedicelli, G. Bono, B. Lemasle +15
Aims: The iron abundance gradient in the Galactic stellar disk provides fundamental constraints on the chemical evolution of this important Galaxy component. However the spread aro…
On the distance of the Magellanic Clouds using Cepheid NIR and optical-NIR Period Wesenheit Relations
L. Inno, N. Matsunaga, G. Bono +8
We present the largest near-infrared (NIR) data sets, , ever collected for classical Cepheids in the Magellanic Clouds (MCs). We selected fundamental (FU) and first overtone…
The chemical evolution of the dwarf Spheroidal galaxy Sextans
R. Theler, P. Jablonka, R. Lucchesi +11
We present the analysis of the FLAMES dataset targeting the central 25 arcmin region of the Sextans dSph. This dataset is the third major part of the high resolution spectroscopic…
Determining the Metallicity of Cepheid Stars in the SMC, LMC and the Galaxy
M. Mottini, F. Primas, M. Romaniello +1
The Cepheid Period-Luminosity relation is unquestionably one of the most powerful tools at our disposal for determining the extragalactic distance scale. While significant progress…
Abundance analysis of two extremely metal-poor stars from the Hamburg/ESO Survey
E. Depagne, V. Hill, N. Christlieb +1
We report on the first high spectral resolution analysis of extremely metal-poor halo stars from the Hamburg/ESO objective-prism survey (HES). The spectra were obtained with UVES a…
Oxygen abundances in metal-poor subgiants as determined from [O I], O I and OH lines
A. E. GarcÃa Pérez, M. Asplund, F. Primas +2
The debate on the oxygen abundances of metal-poor stars has its origin in contradictory results obtained using different abundance indicators. To achieve a better understanding of…
Sodium abundances of AGB and RGB stars in galactic globular clusters I. Analysis and results of NGC 2808
Y. Wang, F. Primas, C. Charbonnel +4
Galactic globular clusters (GC) are known to have multiple stellar populations and be characterised by similar chemical features, e.g. O-Na anti-correlation. While second-populatio…
Two distinct ancient components in the Sculptor Dwarf Spheroidal Galaxy: First Results from DART
Eline Tolstoy, M. J. Irwin, A. Helmi +14
We have found evidence for the presence of two distinct ancient stellar components (both geq 10 Gyr old) in the Sculptor dwarf spheroidal galaxy. We used the ESO Wide Field Imager…
On the neutron-capture elements across the Galactic thin disk using Cepheids
R. da Silva, B. Lemasle, G. Bono +19
We present new accurate abundances for five neutron-capture (Y, La, Ce, Nd, Eu) elements in 73 classical Cepheids located across the Galactic thin disk. Individual abundances are b…
The influence of chemical composition on the properties of Cepheid stars. II-The iron content
M. Romaniello, F. Primas, M. Mottini +6
The Cepheid period-luminosity (PL) relation is unquestionably one of the most powerful tools at our disposal for determining the extragalactic distance scale. While significant pro…
Isotopic lithium abundances in five metal-poor disk stars
P. E. Nissen, D. L. Lambert, F. Primas +1
High resolution (R=110000), very high S/N spectra, centered on the 6707.8A LiI line have been obtained with the ESO Coude Echelle Spectrometer for five, metal-poor (-0.8 < [Fe/H] <…
On the alpha-element gradients of the Galactic thin disk using Cepheids
K. Genovali, B. Lemasle, R. da Silva +16
We present new homogeneous measurements of Na, Al and three alpha-elements (Mg, Si, Ca) for 75 Galactic Cepheids. The abundances are based on high spectral resolution (R ~ 38,000)…
The extreme r-element rich, iron-poor halo giant CS31082-001: Implications for the r-process site(s) and radioactive cosmochronology
V. Hill, B. Plez, R. Cayrel +10
We present a high-resolution spectroscopic analysis of the bright (V=11.7), extreme halo giant CS31082-001 ([Fe/H] = -2.9), obtained in an ESO-VLT Large Programme dedicated to very…
On a new and homogeneous metallicity scale for Galactic classical Cepheids - I. Physical parameters
B. Proxauf, R. da Silva, V. V. Kovtyukh +23
We gathered more than 1130 high-resolution optical spectra for more than 250 Galactic classical Cepheids. The spectra were collected with different optical spectrographs: UVES at V…
Stroemgren metallicity calibration: the m1, b-y relation
A. Calamida, G. Bono, P. B. Stetson +15
We performed a new calibration of the Stroemgren metallicity index m1 based on the b-y color of cluster red giant stars. The current Metallicity-Index-Color relation is not linear…
Age-metallicity relation and Chemical evolution of the LMC from UVES spectra of Globular Cluster giants
V. Hill, P. François, M. Spite +2
We report on the first high-resolution spectroscopy of 10 giants in LMC Globular Clusters in a wide age range, obtained with the newly commissioned spectrograph UVES at VLT UT2. Th…
Determination of robust metallicities for metal-rich red giant branch stars
C. Liu, G. Ruchti, S. Feltzing +1
The study of the Milky Way relies on our ability to interpret the light from stars correctly. This calls for a reinvestigation of how reliably we can determine, e.g., iron abundanc…
First stars XVI. STIS/HST abundances of heavy-elements in the uranium-rich star CS 31082-001
C. Siqueira Mello, M. Spite, B. Barbuy +14
Detailed abundances of the elements produced by r-process nucleosynthesis in various circumstances are our best observational clues to their origin, since the site(s) of r-element…