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381. General Catalog of mean radial velocities
ID:
ivo://CDS.VizieR/III/213
Title:
General Catalog of mean radial velocities
Short Name:
III/213
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a catalogue of mean radial velocities for Galactic stars which supplements the catalogue WEB (1998, See Cat. <III/190>) with observations published through december 1990. The catalogue contains new mean velocities for 36145 stars, among which 20574 are new. Only observations obtained with adequate spectral resolution and standardized to the IAU or Wilson (1953, Cat. <III/21>) velocity systems have been used. Entries in the WEB mean radial velocities catalogue have been taken to represent the mean of earlier measurements, to which the new data have been added. The sources of new data are referenced. To make easier the work of users, we have included in our catalogue the results of the catalogue WEB with the agreement of the author. This catalogue supersedes the previous version numbered <III/161>.
383. Geneva-Copenhagen Survey of Solar neighbourhood
ID:
ivo://CDS.VizieR/V/117A
Title:
Geneva-Copenhagen Survey of Solar neighbourhood
Short Name:
V/117A
Date:
21 Oct 2021
Publisher:
CDS
Description:
(from paper II, 2007) Ages, metallicities, space velocities, and Galactic orbits of stars in the Solar neighbourhood are fundamental observational constraints on models of galactic disk evolution. Understanding and minimising systematic errors and sample selection biases in the data is crucial for their interpretation. We aim to consolidate the calibrations of uvbyb photometry into T_eff_, [Fe/H], distance, and age for F and G stars and rediscuss the results of the Geneva-Copenhagen Survey (GCS, Nordstrom et al., 2004, paper I) in terms of the evolution of the disk. We use recent V-K photometry, angular diameters, high-resolution spectroscopy, Hipparcos parallaxes, and extensive numerical simulations to re-examine and verify the temperature, metallicity, distance, and reddening calibrations for the uvbyb system. We also highlight the selection effects inherent in the apparent-magnitude limited GCS sample. We substantially improve the T_eff_ and [Fe/H] calibrations for early F stars, where spectroscopic temperatures have large systematic errors. A slight offset of the GCS photometry and the non-standard helium abundance of the Hyades invalidate its use for checking metallicity or age scales; however, the distances, reddenings, metallicities, and age scale for GCS field stars require minor corrections only. Our recomputed ages are in excellent agreement with the independent determinations by Takeda et al. (2007ApJS..168..297T), indicating that isochrone ages can now be reliably determined. The revised G-dwarf metallicity distribution remains incompatible with closed-box models, and the age-metallicity relation for the thin disk remains almost flat, with large and real scatter at all ages sigma_intrinsic=0.20 dex). Dynamical heating of the thin disk continues throughout its life; specific in-plane dynamical effects dominate the evolution of the U and V velocities, while the W velocities remain random at all ages. When assigning thick and thin-disk membership for stars from kinematic criteria, parameters for the oldest stars should be used to characterise the thin disk.
384. Geneva-Copenhagen Survey of Solar neighbourhood III
ID:
ivo://CDS.VizieR/V/130
Title:
Geneva-Copenhagen Survey of Solar neighbourhood III
Short Name:
V/130
Date:
21 Oct 2021
Publisher:
CDS
Description:
Ages, chemical compositions, velocity vectors, and Galactic orbits for stars in the solar neighbourhood are fundamental test data for models of Galactic evolution. The Geneva-Copenhagen Survey of the Solar neighbourhood (Nordstrom et al. 2004A&A...418..989N; GCS), a magnitude-complete, kinematically unbiased sample of 16,682 nearby F and G dwarfs, is the largest available sample with complete data for stars with ages spanning that of the disk. We aim to improve the accuracy of the GCS data by implementing the recent revision of the Hipparcos parallaxes. The new parallaxes yield improved astrometric distances for 12,506 stars in the GCS. We also use the parallaxes to verify the distance calibration for uvbyHbeta photometry by Holmberg et al. (2007A&A...475..519H; GCS II, Cat. VI/117). We add new selection criteria to exclude evolved cool stars giving unreliable results and derive distances for 3,580 stars with large parallax errors or not observed by Hipparcos. We also check the GCS II scales of T_eff_ and [Fe/H] and find no need for change. From the new distances we compute revised Mv, U, V, W, and Galactic orbital parameters for 13,520 GCS stars. We also recompute stellar ages with the new values of Mv from the Padova stellar evolution models used in GCS I-II, and compare them with ages from the Yale-Yonsei and Victoria-Regina models. Finally, we compare the observed age-velocity relation in W with three simulated disk heating scenarios to show the potential of the data. With these revisions, the basic data for the GCS stars should now be as reliable as is possible with existing techniques. Further improvement must await consolidation of the T_eff_ scale from angular diameters and fluxes, and the Gaia trigonometric parallaxes. We discuss the conditions for improving computed stellar ages from new input data, and for distinguishing different disk heating scenarios from data sets of the size and precision of the GCS.
385. Geneva-Copenhagen survey re-analysis
ID:
ivo://CDS.VizieR/J/A+A/530/A138
Title:
Geneva-Copenhagen survey re-analysis
Short Name:
J/A+A/530/A138
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a re-analysis of the Geneva-Copenhagen survey, benefiting from the infrared flux method to improve upon the accuracy of the derived stellar effective temperatures and using the latter to build a consistent and improved metallicity scale. Metallicities are calibrated on high-resolution spectroscopy and checked against four open clusters and a moving group, showing excellent consistency. The new temperature and metallicity scales provide a better match to theoretical isochrones, which are used for a Bayesian analysis of stellar ages. With respect to previous analyses, our stars are on average 100K hotter and 0.1dex more metal rich, shifting the peak of the metallicity distribution function around the solar value. From Stromgren photometry we are able to derive for the first time a proxy for [Fe] abundances, which enables for a tentative dissection of the chemical thin and thick disc. We find evidence for the latter being composed of an old, mildly but systematically alpha-enhanced population extending to super solar metallicities, in agreement with spectroscopic studies. Our revision offers the largest existing kinematically unbiased sample of the solar neighbourhood that contains full information on kinematics, metallicities and ages and thus provides better constraints on the physical processes relevant in the build-up of the Milky Way disc, enabling a better understanding of the Sun in a Galactic context.
386. GES: multi-line spectroscopic binary candidates
ID:
ivo://CDS.VizieR/J/A+A/608/A95
Title:
GES: multi-line spectroscopic binary candidates
Short Name:
J/A+A/608/A95
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Gaia-ESO Survey (GES) is a large spectroscopic survey that provides a unique opportunity to study the distribution of spectroscopic multiple systems among different populations of the Galaxy. Aims. Our aim is to detect binarity/multiplicity for stars targeted by the GES from the analysis of the cross-correlation functions (CCFs) of the GES spectra with spectral templates. We developed a method based on the computation of the CCF successive derivatives to detect multiple peaks and determine their radial velocities, even when the peaks are strongly blended. The parameters of the detection of extrema (DOE) code have been optimized for each GES GIRAFFE and UVES setup to maximize detection. The DOE code therefore allows to automatically detect multiple line spectroscopic binaries (SBn, n>=2). We apply this method on the fourth GES internal data release and detect 354 SBn candidates (342 SB2, 11 SB3, and even one SB4), including only nine SBs known in the literature. This implies that about 98% of these SBn candidates are new because of their faint visual magnitude that can reach V=19. Visual inspection of the SBn candidate spectra reveals that the most probable candidates have indeed a composite spectrum. Among the SB2 candidates, an orbital solution could be computed for two previously unknown binaries: CNAME 06404608+0949173 (known as V642 Mon) in NGC 2264 and CNAME 19013257-0027338 in Berkeley 81 (Be 81). A detailed analysis of the unique SB4 (four peaks in the CCF) reveals that CNAME 08414659-5303449 (HD 74438) in the open cluster IC 2391 is a physically bound stellar quadruple system. The SB candidates belonging to stellar clusters are reviewed in detail to discard false detections. We suggest that atmospheric parameters should not be used for these system components; SB-specific pipelines should be used instead. Our implementation of an automatic detection of spectroscopic binaries within the GES has allowed the efficient discovery of many new multiple systems. With the detection of the SB1 candidates that will be the subject of a forthcoming paper, the study of the statistical and physical properties of the spectroscopic multiple systems will soon be possible for the entire GES sample.
387. GHASP: H{alpha} data cubes for 108 galaxies
ID:
ivo://CDS.VizieR/J/MNRAS/388/500
Title:
GHASP: H{alpha} data cubes for 108 galaxies
Short Name:
J/MNRAS/388/500
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the Fabry-Perot observations obtained for a new set of 108 galaxies in the frame of the Gassendi H{alpha} survey of SPirals (GHASP). The GHASP survey consists of 3D H{alpha} data cubes for 203 spiral and irregular galaxies, covering a large range in morphological types and absolute magnitudes, for kinematics analysis. The new set of data presented here completes the survey. The GHASP sample is by now the largest sample of Fabry-Perot data ever published. The analysis of the whole GHASP sample will be done in forthcoming papers. Using adaptive binning techniques based on Voronoi tessellations, we have derived H{alpha} data cubes from which are computed H{alpha} maps, radial velocity fields as well as residual velocity fields, position-velocity diagrams, rotation curves and the kinematical parameters for almost all galaxies.
388. GHASP: H{alpha} data cubes for 97 galaxies
ID:
ivo://CDS.VizieR/J/MNRAS/390/466
Title:
GHASP: H{alpha} data cubes for 97 galaxies
Short Name:
J/MNRAS/390/466
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Gassendi HAlpha survey of SPirals survey (GHASP) consists of 3D H{alpha} data cubes for 203 spiral and irregular galaxies, covering a large range in morphological types and absolute magnitudes, for kinematics analysis. It is the largest sample of Fabry-Perot data published up to now. In order to provide an homogenous sample, reduced and analysed using the same procedure, we present in this paper the new reduction and analysis for a set of 97 galaxies already published in previous papers but now using the new data reduction procedure adopted for the whole sample. The GHASP survey is now achieved and the whole sample is reduced using the adaptive binning techniques based on Voronoi tessellations. We have derived H{alpha} data cubes from which are computed H{alpha} maps, radial velocity fields as well as residual velocity fields, position-velocity diagrams, rotation curves and kinematical parameters for almost all galaxies. The rotation curves, the kinematical parameters and their uncertainties are computed homogeneously using the new method based on the power spectrum of the residual velocity field. This paper provides the kinematical parameters for the whole sample. For the first time, the integrated H{alpha} profiles have been computed and are presented for the whole sample. The total H{alpha} fluxes deduced from these profiles have been used in order to provide a flux calibration for the 203 GHASP galaxies. This paper confirms the conclusions already drawn from half the sample concerning (i) the increased accuracy of position angles measurements using kinematical data, (ii) the difficulty to have robust determinations of both morphological and kinematical inclinations in particular for low-inclination galaxies and (iii) the very good agreement between the Tully-Fisher relationship derived from our data and previous determinations found in the literature.
389. GHASP: H{alpha} data cubes for 153 galaxies
ID:
ivo://CDS.VizieR/J/MNRAS/401/2113
Title:
GHASP: H{alpha} data cubes for 153 galaxies
Short Name:
J/MNRAS/401/2113
Date:
21 Oct 2021
Publisher:
CDS
Description:
Due to their large distances, high-redshift galaxies are observed at a very low spatial resolution. In order to disentangle the evolution of galaxy kinematics from low-resolution effects, we have used Fabry-Perot 3D H{alpha} data cubes of 153 nearby isolated galaxies selected from the Gassendi H{alpha} survey of SPirals (GHASP) to simulate data cubes of galaxies at redshift z=1.7 using a pixel size of 0.125" and a 0.5" seeing. We have derived H{alpha} flux, velocity and velocity dispersion maps.
390. 1.4GHz flux densities of Abell 2255 galaxies
ID:
ivo://CDS.VizieR/J/AJ/125/2427
Title:
1.4GHz flux densities of Abell 2255 galaxies
Short Name:
J/AJ/125/2427
Date:
21 Oct 2021
Publisher:
CDS
Description:
Deep VLA 1.4GHz radio continuum imaging of Abell 2255 is presented. This cluster is among the better nearby candidates for rich cluster-cluster merger systems, with evidence including an elongated X-ray morphology, the presence of a radio halo, and substructure present in its galaxy distribution. Our radio observations reach an rms sensitivity of ~40{mu}Jy/beam, enabling us to detect (at 5{sigma}) star formation rates as low as 1.4M_{sun}_/yr from the center of the cluster out to a radial distance of 3h^-1^_75_Mpc. The radio data are complemented by optical imaging and a large spectroscopic database, allowing us to separate all galaxies with M_Rc_<=-20 0 into cluster members and foreground/background galaxies. The spectra are also used to associate the galaxies' radio emission with either star formation or active galactic nuclei (AGNs). We compare the resulting cluster radio galaxy population with those of 19 other nearby Abell clusters and find strong evidence for an increase in the frequency of radio galaxies in Abell 2255. This increase is seen in two separate types of galaxies: powerful radio AGNs and optically faint star-forming galaxies. The optical spectra of the latter often indicate current or recent starbursts, and these galaxies appear to be distributed along an axis perpendicular to the probable merger axis. We assess these factors in light of models of galaxy evolution and suggest that the cluster-cluster merger is responsible for triggering galaxy activity in Abell 2255.

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