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851. alpha Persei, Pleiades and Praesepe clusters
ID:
ivo://CDS.VizieR/J/A+A/628/A66
Title:
alpha Persei, Pleiades and Praesepe clusters
Short Name:
J/A+A/628/A66
Date:
21 Oct 2021
Publisher:
CDS
Description:
Our scientific goal is to provide revised membership lists of the alpha Per, Pleiades, and Praesepe clusters exploiting the second data release of Gaia and produce five-dimensional maps ({alpha}, {delta}, {pi}, {mu}_{alpha}_cos{delta}, {mu}_{delta}_) of these clusters. We implemented the kinematic method combined with the statistical treatment of parallaxes and proper motions to identify astrometric member candidates of three of the most nearby and best studied open clusters in the sky. We cross-correlated the Gaia catalogue with large-scale public surveys to complement the astrometry of Gaia with multi-band photometry from the optical to the mid-infrared. We identified 517, 1248, and 721 bona fide astrometric member candidates inside the tidal radius of alpha Per, the Pleiades, and Praesepe, respectively. We cross-matched our final samples with catalogues from previous surveys to address the level of completeness. We update the main physical properties of the clusters, including mean distance and velocity, as well as core, half-mass, and tidal radii. We infer updated ages from the white dwarf members of the Pleiades and Praesepe. We derive the luminosity and mass functions of the three clusters and compare them to the field mass function. We compute the positions in space of all member candidates in the three regions to investigate their distribution in space. We provide updated distances and kinematics for the three clusters. We identify a list of members in the alpha Per, Pleiades, and Praesepe clusters from the most massive stars all the way down to the hydrogen-burning limit with a higher confidence and better astrometry than previous studies. We produce complete 5D maps of stellar and substellar bona fide members in these three regions. The photometric sequences derived in several colour-magnitude diagrams represent benchmark cluster sequences at ages from 90 to 600Myr. We note the presence of a stream around the Pleiades cluster extending up to 40 pc from the cluster centre.
852. {alpha} Scl and HD 170973 abundances
ID:
ivo://CDS.VizieR/J/A+A/367/859
Title:
{alpha} Scl and HD 170973 abundances
Short Name:
J/A+A/367/859
Date:
21 Oct 2021
Publisher:
CDS
Description:
Fine analyses of the magnetic CP stars {alpha} Scl and HD 170973 are presented using ATLAS9 model atmospheres which have same bulk metallicity as the deduced abundances. The light elements are mostly solar except for silicon, and all the heavier elements except nickel in HD 170973, which is solar, are greatly overabundant. The iron peak elements are typically 10 times overabundant, Sr is of order of 1000 times solar, Y and Zr are of order of 100 times solar. The rare earths are 1000 or more times overabundant.
853. alpha Vir RV and EW variations
ID:
ivo://CDS.VizieR/J/A+A/590/A54
Title:
alpha Vir RV and EW variations
Short Name:
J/A+A/590/A54
Date:
21 Oct 2021
Publisher:
CDS
Description:
Alpha Virginis (Spica) is a B-type binary system whose proximity and brightness allow detailed investigations of the internal structure and evolution of stars undergoing time-variable tidal interactions. Previous studies have led to the conclusion that the internal structure of Spica's primary star may be more centrally condensed than predicted by theoretical models of single stars, raising the possibility that the interactions could lead to effects that are currently neglected in structure and evolution calculations. The key parameters in confirming this result are the values of the orbital eccentricity e, the apsidal period U, and the primary star's radius, R1. The aim of this paper is to analyze the impact that Spica's line profile variability has on the derivation of its orbital elements and to explore the use of the variability for constraining R1.
854. ALPINE-ALMA [CII] survey. IR luminosity
ID:
ivo://CDS.VizieR/J/A+A/643/A4
Title:
ALPINE-ALMA [CII] survey. IR luminosity
Short Name:
J/A+A/643/A4
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present dust attenuation properties of spectroscopically confirmed star forming galaxies on the main sequence at a redshift of ~4.4-5.8. Our analyses are based on the far infrared continuum observations of 118 galaxies at rest-frame 158 {mu}m obtained with the Atacama Large Millimeter Array (ALMA) Large Program to INvestigate [CII] at Early times (ALPINE). We study the connection between the ultraviolet (UV) spectral slope ({beta}), stellar mass (M*), and infrared excess (IRX=L_IR_/L_UV_). Twenty-three galaxies are individually detected in the continuum at > 3.5{sigma} significance. We perform a stacking analysis using both detections and nondetections to study the average dust attenuation properties at z~4.4-5.8. The individual detections and stacks show that the IRX-{beta} relation at z~5 is consistent with a steeper dust attenuation curve than typically found at lower redshifts (z<4). The attenuation curve is similar to or even steeper than that of the extinction curve of the Small Magellanic Cloud. This systematic change of the IRX-{beta} relation as a function of redshift suggests an evolution of dust attenuation properties at z>4. Similarly, we find that our galaxies have lower IRX values, up to 1dex on average, at a fixed mass compared to previously studied IRX-M* relations at z<=4, albeit with significant scatter. This implies a lower obscured fraction of star formation than at lower redshifts. Our results suggest that dust properties of UV-selected star forming galaxies at z>=4 are characterised by (i) a steeper attenuation curve than at z<=4, and (ii) a rapidly decreasing dust obscured fraction of star formation as a function of redshift. Nevertheless, even among this UV-selected sample, massive galaxies (logM*/M_{sun}_>10) at z~5-6 already exhibit an obscured fraction of star formation of ~45%, indicating a rapid build-up of dust during the epoch of reionization.
855. ALPINE DR1 merged catalog
ID:
ivo://CDS.VizieR/J/A+A/643/A2
Title:
ALPINE DR1 merged catalog
Short Name:
J/A+A/643/A2
Date:
21 Oct 2021
Publisher:
CDS
Description:
The ALPINE-ALMA large program targets the [CII] 158um line and the far-infrared continuum in 118 spectroscopically confirmed star-forming galaxies between z=4.4 and z=5.9. It represents the first large [CII] statistical sample built in this redshift range. We present details of the data processing and the construction of the catalogs. We detected 23 of our targets in the continuum. To derive accurate infrared luminosities and obscured star formation rates, we measured the conversion factor from the ALMA 158um rest-frame dust continuum luminosity to the total infrared luminosity (LIR) after constraining the dust spectral energy distribution by stacking a photometric sample similar to ALPINE in ancillary single-dish far-infrared data. We found that our continuum detections have a median LIR of 4.4x10^11^L_{sun}_. We also detected 57 additional continuum sources in our ALMA pointings. They are at lower redshift than the ALPINE targets, with a mean photometric redshift of 2.5+/-0.2. We measured the 850um number counts between 0.35 and 3.5mJy, improving the current interferometric constraints in this flux density range. We found a slope break in the number counts around 3mJy with a shallower slope below this value. More than 40% of the cosmic infrared background is emitted by sources brighter than 0.35mJy. Finally, we detected the [CII] line in 75 of our targets. Their median [CII] luminosity is 4.8x108L_{sun}_ and their median full width at half maximum is 252km/s. After measuring the mean obscured SFR in various [CII] luminosity bins by stacking ALPINE continuum data, we find a good agreement between our data and the local and predicted SFR-L[CII] relations of De Looze et al. (2014A&A...568A..62D) and Lagache et al. (2018A&A...609A.130L).
856. Amalthea and Thebe CCD astrometric obs.
ID:
ivo://CDS.VizieR/J/A+A/437/1147
Title:
Amalthea and Thebe CCD astrometric obs.
Short Name:
J/A+A/437/1147
Date:
21 Oct 2021
Publisher:
CDS
Description:
This paper presents the results of observations of Jupiter's satellites Amalthea and Thebe made in 1995, 1996 and 2001 at the Laboratorio Nacional de Astrofisica (LNA), Brazil. The observations were made in visible light wavelengths with a 1.6m reflector telescope and the light of Jupiter was covered by a mask placed near the CCD surface. The already published positions for 1995, whose astrometric reduction used the Galilean satellites, are now reduced using the stars in the CCD fields like the new positions of 1996 and 2001. The 2001 data are much better than those obtained in 1995, and that those from 1996 show large residuals. Considering the 310 frames observed, the mean residual is about 0.01" and the standard deviation is about 0.15".
857. A mapping survey of massive CO cores
ID:
ivo://CDS.VizieR/J/MNRAS/391/869
Title:
A mapping survey of massive CO cores
Short Name:
J/MNRAS/391/869
Date:
21 Oct 2021
Publisher:
CDS
Description:
We mapped 21 star-forming regions with the ^12^CO, ^13^CO and C^18^O (1-0) lines using the 13.7-m telescope of Purple Mount Observatory. This mapping survey resolved 53 ^13^CO cores, of which 22 are sourceless. We obtained the physical parameters of these cores. The relation between ^13^CO linewidth and core size and that between column density and core size were analysed. The cores 00211+6549-1 and 22566+5830 were found to have outflows. Systematic VLSR shifts were detected in nine regions: 00211+6549, 00232+6437, 05168+3634, 19199+1358, 20160+3911, 22566+5830, 23042+6000, S146 and S270. Signatures of infall and cloud collision were found in regions 18507+0121 and 19199+1358, respectively. We studied the mass function of these ^13^CO cores. The core masses range from 3.40 to 4.64x10^4^M_{sun}_, and the core mass function is a power-law distribution of index -0.82+/-0.04.
858. A 2MASS view of the Sgr dSph. VI.
ID:
ivo://CDS.VizieR/J/ApJ/708/1290
Title:
A 2MASS view of the Sgr dSph. VI.
Short Name:
J/ApJ/708/1290
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present high-resolution spectroscopic measurements of the abundances of the {alpha} element titanium (Ti) and s-process elements yttrium (Y) and lanthanum (La) for 59 candidate M giant members of the Sagittarius (Sgr) dwarf spheroidal (dSph) + tidal tail system pre-selected on the basis of position and radial velocity (RV). As expected, the majority of these stars show peculiar abundance patterns compared to those of nominal Milky Way (MW) stars, but as a group, the stars form a coherent picture of chemical enrichment of the Sgr dSph from [Fe/H]=-1.4 to solar abundance. Finally, we analyze the chemical abundances of a moving group of M giants among the Sgr leading arm stars at the North Galactic Cap, but having RVs unlike the infalling Sgr leading arm debris there. Through use of "chemical fingerprinting," we conclude that these mostly receding northern hemisphere M giants also are Sgr stars, likely trailing arm debris overlapping the Sgr leading arm in the north.
859. AMBRE catalogue of sulfur abundances
ID:
ivo://CDS.VizieR/J/A+A/647/A162
Title:
AMBRE catalogue of sulfur abundances
Short Name:
J/A+A/647/A162
Date:
21 Oct 2021
Publisher:
CDS
Description:
Sulfur is a volatile chemical element that plays an important role in tracing the chemical evolution of the Milky Way and external galaxies. However, its nucleosynthesis origin and abundance variations in the Galaxy are still unclear because the number of available stellar sulfur abundance measurements is currently rather small. The goal of the present article is to accurately and precisely study the sulfur content of large number of stars located in the solar neighbourhood. We use the parametrisation of thousands of high-resolution stellar spectra provided by the AMBRE Project, and combine it with the automated abundance determination GAUGUIN to derive local thermodynamic equilibrium (LTE) sulfur abundances for 1855 slow-rotating FGK-type stars. This is the largest and most precise catalogue of sulfur abundances published to date. It covers a metallicity domain as high as ~2.5dex starting at [M/H]<~-2.0dex. We find that the sulfur-to-iron abundances ratio is compatible with a plateau-like distribution in the metal-poor regime, and then starts to decrease continuously at [M/H]~-1.0dex. This decrease continues towards negative values for supersolar metallicity stars as recently reported for magnesium and as predicted by Galactic chemical evolution models. Moreover, sulfur-rich stars having metallicities in the range [-1.0,-0.5] have very different kinematical and orbital properties with respect to more metal-rich and sulfur-poor ones. Two disc components, associated with the thin and thick discs, are thus seen independently in kinematics and sulfur abundances. The sulfur radial gradients in the Galactic discs have also been estimated. Finally, the enrichment in sulfur with respect to iron is nicely correlated with stellar ages: older metal-poor stars have higher [S/M] ratios than younger metal-rich ones. This work has confirmed that sulfur is an {alpha}-element that could be considered to explore the Galactic populations properties. For the first time, a chemo-dynamical study from the sulfur abundance point of view, as a stand-alone chemical element, is performed.
860. AMBRE project. FEROS archived spectra
ID:
ivo://CDS.VizieR/J/A+A/542/A48
Title:
AMBRE project. FEROS archived spectra
Short Name:
J/A+A/542/A48
Date:
21 Oct 2021
Publisher:
CDS
Description:
The AMBRE Project is a collaboration between the European Southern Observatory (ESO) and the Observatoire de la Cote d'Azur (OCA) that has been established in order to carry out the determination of stellar atmospheric parameters for the archived spectra of four ESO spectrographs. The analysis of the FEROS archived spectra for their stellar parameters (effective temperatures, surface gravities, global metallicities, alpha element to iron ratios and radial velocities) has been completed in the first phase of the AMBRE Project. From the complete ESO:FEROS archive dataset that was received, a total of 21551 scientific spectra have been identified, covering the period 2005 to 2010. These spectra correspond to 6285 stars. The determination of the stellar parameters was carried out using the stellar parameterisation algorithm, MATISSE (MATrix Inversion for Spectral SynthEsis), which has been developed at OCA to be used in the analysis of large scale spectroscopic studies in galactic archaeology. An analysis pipeline has been constructed that integrates spectral normalisation, cleaning and radial velocity correction procedures in order that the FEROS spectra could be analysed automatically with MATISSE to obtain the stellar parameters. The synthetic grid against which the MATISSE analysis is carried out is currently constrained to parameters of FGKM stars only. Stellar atmospheric parameters, effective temperature, surface gravity, metallicity and alpha element abundances, were determined for 6508 (30.2%) of the FEROS archived spectra (~3087 stars). Radial velocities were determined for 11963 (56%) of the archived spectra. 2370 (11%) spectra could not be analysed within the pipeline due to very low signal-to-noise ratios or missing spectral orders. 12673 spectra (58.8%) were analysed in the pipeline but their parameters were discarded based on quality criteria and error analysis determined within the automated process. The majority of these rejected spectra were found to have broad spectral features, as probed both by the direct measurement of the features and cross-correlation function breadths, indicating that they may be hot and/or fast rotating stars, which are not considered within the adopted reference synthetic spectra grid. The current configuration of the synthetic spectra grid is devoted to slow-rotating FGKM stars. Hence non-standard spectra (binaries, chemically peculiar stars etc.) that could not be identified may pollute the analysis.