- ID:
- ivo://CDS.VizieR/J/ApJ/497/188
- Title:
- A103, A118 and A114 morphological studies
- Short Name:
- J/ApJ/497/188
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of a program to study the detailed morphologies of galaxies in intermediate-redshift clusters and hence understand the physical origin of the enhanced star formation seen in the environments at earlier epochs. Deep, high-resolution imagery has been obtained of three rich clusters, AC 103, AC 118 and AC 114 at z=0.31, through the R (F702W) filter of the Wide Field Planetary Camera (WFPC2) of the Hubble Space Telescope (HST).
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- ID:
- ivo://CDS.VizieR/J/A+AS/137/521
- Title:
- 8500-8750{AA} high resolution spectroscopy
- Short Name:
- J/A+AS/137/521
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an Echelle+CCD high resolution spectroscopic atlas mapping the MKK classification system over the wavelength interval lambda 8500-8750 A, centered on the near-IR triplet of Ca II. Table 2 lists all the 131 program stars with basic informations (magnitudes, coordinates, spectral types, metallicities, rotational velocities, variabilities) and the journal of observations; Table 3 shows our mapping of the MKK scheme in terms of spectral and luminosity classes; Table 4 lists the major un-blended absorption lines which we identified in our spectra
- ID:
- ivo://CDS.VizieR/J/A+A/406/995
- Title:
- 8500-8750{AA} high resolution spectroscopy. IV.
- Short Name:
- J/A+A/406/995
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A library of high resolution spectra of MK standard and reference stars, observed in support to the GAIA mission, is presented. The aim of this paper is to integrate the MK mapping of Paper I (<J/A+AS/137/521>) of this series as well as to consider stars over a wider range of metallicities. Radial velocities are measured for all the target stars.
- ID:
- ivo://CDS.VizieR/J/A+A/657/A25
- Title:
- A521 and Cosmic Snake ALMA abd HST images
- Short Name:
- J/A+A/657/A25
- Date:
- 16 Mar 2022 13:03:06
- Publisher:
- CDS
- Description:
- We study the spatially resolved physical properties of the Cosmic Snake arc in MACS J1206.2-0847 and the arc in Abell 0521 (A521). These are two strongly lensed galaxies at redshifts z=1.036 and z=1.044. We used observations of the Hubble Space Telescope (HST) and the Atacama Large Millimeter/submillimeter Array (ALMA). The former gives access to the star formation rate (SFR) and stellar mass (M*), and the latter to the H_2_ molecular gas mass (Mmol). HST and ALMA observations have similar angular resolutions of 0.15"-0.2", which with the help of strong gravitational lensing enable us to reach spatial resolutions down to ~30pc and ~100pc in these two galaxies, respectively. These resolutions are close to the resolution of observations of nearby galaxies. We study the radial profiles of SFR, M*, and Mmol surface densities of these high-redshift galaxies and compare the corresponding exponential scale lengths with those of local galaxies. We find that the scale lengths in the Cosmic Snake are about 0.5kpc-1.5kpc, and they are 3 to 10 times larger in A521. This is a significant difference knowing that the two galaxies have comparable integrated properties. These high-redshift scale lengths are nevertheless comparable to those of local galaxies, which cover a wide distribution. The particularity of our high-redshift radial profiles is the normalisation of the Mmol surface density profiles (Sigma Mmol), which are offset by up to a factor of 20 with respect to the profiles of z=0 counterparts. The SFR surface density profiles are also offset by the same factor as {SIGMA}Mmol, as expected from the Kennicutt-Schmidt law.
- ID:
- ivo://CDS.VizieR/J/A+A/523/A71
- Title:
- A and F stars abundances in the Hyades
- Short Name:
- J/A+A/523/A71
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Abundances of 15 chemical elements have been derived for 28 F and 16 A stars members of the Hyades open cluster in order to set constraints on self-consistent evolutionary models that include radiative and turbulent diffusion A spectral synthesis, iterative procedure was applied to derive the abundances from selected high-quality lines in high-resolution, high-signal-to-noise spectra obtained with SOPHIE and AURELIE at the Observatoire de Haute Provence.
- ID:
- ivo://CDS.VizieR/J/A+A/628/A67
- Title:
- 15273{AA} near-infrared DIB
- Short Name:
- J/A+A/628/A67
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The latest SDSS/APOGEE data release DR14 has provided an increased number of stellar spectra in the H band and associated stellar models using an innovative algorithm known as The Cannon. We took advantage of these novelties to extract the 15273{AA} near-infrared DIB and to study its link with dust extinction and emission. We modified our automated fitting methods dedicated for hot stars and used in earlier studies with some adaptations motivated by the change from early- or intermediate-type stars to red giants. A new method has also been developed to quantify the upper limits on DIB strengths. Careful and thorough examinations of the DIB parameters, the continuum shape and the quality of the adjustment of the model to the data were done. We compared our DIB measurements with the stellar extinctions Av from the Starhorse database. We then compared the resulting DIB-extinction ratio with the dust optical depth derived from Planck data, globally and also separately for nearby off-Plane cloud complexes. Our analysis has led to the production of a catalog containing 124 064 new measurements of the 15273{AA} DIB, allowing us to revisit the correlation between DIB strength and dust reddening.
- ID:
- ivo://CDS.VizieR/J/MNRAS/460/2193
- Title:
- A3407 + A3408 radial velocities
- Short Name:
- J/MNRAS/460/2193
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We carried out a dynamical study of the galaxy cluster pair A3407 and A3408 based on a spectroscopic survey obtained with the 4 metre Blanco telescope at the Cerro Tololo Interamerican Observatory, plus 6dF data, and ROSAT All-Sky Survey. The sample consists of 122 member galaxies brighter than m_R_=20. Our main goal is to probe the galaxy dynamics in this field and verify if the sample constitutes a single galaxy system or corresponds to an ongoing merging process. Statistical tests were applied to clusters members showing that both the composite system A3407 + A3408 as well as each individual cluster have Gaussian velocity distribution. A velocity gradient of ~847+/-114km/s was identified around the principal axis of the projected distribution of galaxies, indicating that the global field may be rotating. Applying the kmm algorithm to the distribution of galaxies, we found that the solution with two clusters is better than the single unit solution at the 99 per cent cl. This is consistent with the X-ray distribution around this field, which shows no common X-ray halo involving A3407 and A3408. We also estimated virial masses and applied a two-body model to probe the dynamics of the pair. The more likely scenario is that in which the pair is gravitationally bound and probably experiences a collapse phase, with the cluster cores crossing in less than ~1h^-1^Gyr, a pre-merger scenario. The complex X-ray morphology, the gas temperature, and some signs of galaxy evolution in A3408 suggest a post-merger scenario, with cores having crossed each other ~1.65h^-1^Gyr ago, as an alternative solution.
- ID:
- ivo://CDS.VizieR/J/ApJS/216/22
- Title:
- 3060-3700{AA} spectra analysis of early-type stars
- Short Name:
- J/ApJS/216/22
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a comprehensive and sensitive unbiased survey of interstellar features in the near-UV range (3050-3700{AA}). We combined a large number of VLT/UVES archival observations of a sample of highly reddened early-type stars -typical diffuse interstellar band targets- and unreddened standards. We stacked the individual observations to obtain a reddened "superspectrum" in the interstellar rest frame with a signal-to-noise ratio exceeding 1500. We compared this to the analogous geocentric and stellar rest frame superspectra as well as to an unreddened superspectrum to find interstellar absorption features. We find 30 known features (11 atomic and 19 molecular) and tentatively detect up to 7 new interstellar absorption lines of unknown origin. Our survey is sensitive to narrow and weak features; telluric residuals preclude us from detecting broader features. For each sightline, we measured fundamental parameters (radial velocities, line widths, and equivalent widths) of the detected interstellar features. We also revisit upper limits for the column densities of small, neutral polycyclic aromatic hydrocarbon molecules that have strong transitions in this wavelength range.
- ID:
- ivo://CDS.VizieR/J/ApJ/850/34
- Title:
- 3000-25000{AA} spectroscopy of nearby M dwarfs
- Short Name:
- J/ApJ/850/34
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Recent studies of the stellar population in the solar neighborhood (<20pc) suggest that there are undetected white dwarfs (WDs) in multiple systems with main-sequence companions. Detecting these hidden stars and obtaining a more complete census of nearby WDs is important for our understanding of stellar and galactic evolution, as well as the study of explosive phenomena. In an attempt to uncover these hidden WDs, we present intermediate resolution spectroscopy over the wavelength range of 3000-25000{AA} of 101 nearby M dwarfs (dMs), observed with the Very Large Telescope X-Shooter spectrograph. For each star we search for a hot component superimposed on the dM spectrum. X-Shooter has excellent blue sensitivity and thus can reveal a faint hot WD despite the brightness of its red companion. Visual examination shows no clear evidence of a WD in any of the spectra. We place upper limits on the effective temperatures of WDs that may still be hiding by fitting dM templates to the spectra and modeling the WD spectra. On average our survey is sensitive to WDs hotter than about 5300K. This suggests that the frequency of WD companions of Teff>~5300K with separation of the order of <~50 au among the local dM population is <3% at the 95% confidence level.
- ID:
- ivo://nasa.heasarc/aavsovsx
- Title:
- AAVSO International Variable Star Index
- Short Name:
- AAVSOVSX
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This database table contains Galactic stars known or suspected to be variable. It lists all stars that have an entry in the American Association of Variable Star Observers' (AAVSO) International Variable Star Index (VSX; <a href="http://www.aavso.org/vsx">http://www.aavso.org/vsx</a>). It consisted initially of the General Catalogue of Variable Stars (GCVS) and the New Catalogue of Suspected Variables (NSV) and was then supplemented with a large number of variable star catalogues, as well as individual variable star discoveries or variables found in the literature. Effort has also been invested to update the entries with the latest information regarding position, type and period and to remove duplicates. The VSX database is being continually updated and maintained. For historical reasons some objects outside of the Galaxy have been included. This table was created by the HEASARC based on the <a href="https://cdsarc.cds.unistra.fr/ftp/cats/B/vsx">CDS catalog B/vsx</a>. The CDS updates it regularly, and this HEASARC version is accordingly updated within a week of such updates. This is a service provided by NASA HEASARC .
- ID:
- ivo://CDS.VizieR/B/vsx
- Title:
- AAVSO International Variable Star Index VSX
- Short Name:
- B/vsx
- Date:
- 07 Mar 2022 08:38:01
- Publisher:
- CDS
- Description:
- This file contains Galactic stars known or suspected to be variable. It lists all stars that have an entry in the AAVSO International Variable Star Index (VSX; http://www.aavso.org/vsx). The database consisted initially of the General Catalogue of Variable Stars (GCVS) and the New Catalogue of Suspected Variables (NSV) and was then supplemented with a large number of variable star catalogues, as well as individual variable star discoveries or variables found in the literature. Effort has also been invested to update the entries with the latest information regarding position, type and period and to remove duplicates. The VSX database is being continually updated and maintained. For historical reasons some objects outside of the Galaxy have been included.
- ID:
- ivo://org.gavo.dc/apass/q/cone
- Title:
- AAVSO Photometric All Sky Survey (APASS) DR10
- Short Name:
- APASS DR10 cone
- Date:
- 23 Mar 2022 13:13:11
- Publisher:
- The GAVO DC team
- Description:
- AAVSO Photometric All-Sky Survey (APASS), underway since 2010, covers the entire sky from 7.5 < V < 16.5 magnitude, and in the BVugrizY bandpasses. A northern and a southern site are used, each with twin ASA 20cm astrographs and Apogee Aspen CG16m cameras, covering 2.9x2.9 square degrees with 2.6arcsec pixels. Landolt and SDSS standards are used for all-sky solutions, with typical 0.02mag calibration errors on the bright end. Data Release 10 is a complete reprocessing of all 500K images taken with the system, including hundreds of nights not part of DR9. Sextractor is used for star finding and centroiding; DAOPHOT is used for aperture photometry; the astrometry.net plate-solving library is used for basic astrometry, supplanted with more precise WCS that utilizes knowledge of the optical train distortions. With these changes, DR10 includes many more stars than prior releases. More information is available at http://www.aavso.org/apass.
- ID:
- ivo://CDS.VizieR/II/336
- Title:
- AAVSO Photometric All Sky Survey (APASS) DR9
- Short Name:
- II/336
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The AAVSO Photometric All Sky Survey (APASS) project is designed to bridge the gap between the shallow Tycho2 two-bandpass photometric catalog that is complete to V=11 and the deeper, but less spatially-complete catalogs like SDSS or PanSTARRS. It can be used for calibration of a specific field; for obtaining spectral information about single sources, determining reddening in a small area of the sky; or even obtaining current-epoch astrometry for rapidly moving objects. The survey is being performed at two locations: near Weed, New Mexico in the Northern Hemisphere; and at CTIO in the Southern Hemisphere. Each site consists of dual bore-sighted 20cm telescopes on a single mount, designed to obtain two bandpasses of information simultaneously. Each telescope covers 9 square degrees of sky with 2.5arcsec pixels, with the main survey taken with B,V,g',r',i' filters and covering the magnitude range 10<V<17. A bright extension is underway, saturating at V=7 and extending the wavelength coverage from u' to Y. The current catalog is Data Release 9 and contains approximately 62 million stars. The American Association of Variable Star Observers is responsible for the overall management of the survey; a team of professional astronomers participate in the data analysis. The project was initially funded by the Robert Martin Ayers Sciences Fund, with a follow-on grant from the National Science Foundation.
- ID:
- ivo://archive.stsci.edu/catalogs/APASS
- Title:
- AAVSO Photometric All Sky Survey ConeSearch
- Short Name:
- APASS CS
- Date:
- 23 Jul 2020 19:59:03
- Publisher:
- Space Telescope Science Institute Archive
- Description:
- All MAST catalog holdings are available via Cone Search endpoints. This service provides access to the MAST mirror of the AAVSO Photometric All Sky Survey All available missions are listed at http://archive.stsci.edu/vo/mast_services.html.
- ID:
- ivo://CDS.VizieR/J/ApJS/192/2
- Title:
- A Bayesian search for binaries in Hipparcos
- Short Name:
- J/ApJS/192/2
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We develop Bayesian statistical methods for discovering and assigning probabilities to non-random (e.g., physical) stellar companions. These companions are either presently bound or were previously bound. The probabilities depend on similarities in corrected proper motion parallel and perpendicular to the brighter component's motion, parallax, and the local phase-space density of field stars. Control experiments are conducted to understand the behavior of false positives. The technique is applied to the Hipparcos Catalogue (Cat. I/239) within 100pc. This is the first all-sky survey to locate escaped companions still drifting along with each other. In the <100pc distance range, ~220 high probability companions with separations between 0.01 and 1pc are found. The first evidence for a population (~300) of companions separated by 1-8pc is found.
- ID:
- ivo://CDS.VizieR/I/65
- Title:
- Abbadia Catalogue between +5{deg}15 and -3{deg}15'
- Short Name:
- I/65
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The catalogue contains the mean positions of 13532 stars observed at the Abbadia Observatory (near Hendaye, France), from observations made at the between 1906 and 1912 with the meridien circle of the observatory. The observations were made mainly for the reduction of the Alger zone of the Astrographic Catalogue. The original catalogue contains also approximative magnitudes which are not reported here.
- ID:
- ivo://CDS.VizieR/I/57
- Title:
- Abbadia Catalogue of 14263 Stars, +16 to +24{deg}
- Short Name:
- I/57
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalog contains meridian circle observations of 14192 reference stars in the Paris Observatory zone of the Astrographic Catalog, +16 to +24deg, made from 1899 to 1906. The original catalog contains also a supplement of 81 stars, which is not included here. The positions have been reduced to 1900.0 on the basis of Newcomb's constants. The probable errors for most stars range from 0.0093s to 0.0161s in right ascension and from 0.096" to 0.162" in declination, depending on the number of observations. In addition to the positions, the catalog contains a running number, the magnitude from the Berlin catalogs, the mean epoch and number of observations, and the BD number.
- ID:
- ivo://CDS.VizieR/J/MNRAS/387/1374
- Title:
- ABCG209 spectroscopic and photometric catalog
- Short Name:
- J/MNRAS/387/1374
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper is aimed at giving an overview of the global properties of the rich cluster of galaxies ABCG 209. This is achieved by complementing the already available data with new medium-resolution spectroscopy and near-infrared (NIR) photometry which allow us to (i) analyse in detail the cluster dynamics, distinguishing among galaxies belonging to different substructures and deriving their individual velocity distributions, using a total sample of 148 galaxies in the cluster region, of which 134 belonging to the cluster; (ii) derive the cluster NIR luminosity function; (iii) study the Kormendy relation and the photometric plane of cluster early-type galaxies (ETGs). Finally we provide an extensive photometric (optical and NIR) and spectroscopic data set for such a complex system to be used in further analyses investigating the nature, formation and evolution of rich clusters of galaxies.
- ID:
- ivo://CDS.VizieR/J/A+AS/129/281
- Title:
- ABCG 85 velocities catalogue
- Short Name:
- J/A+AS/129/281
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalogue of velocities for 551 galaxies (and give the coordinates of 39 stars misclassified as galaxies in our photometric plate catalogue) in a region covering about 100'x100' (0.94x0.94Mpc for an average redshift of 0.0555, assuming H_0_=50km/s/Mpc) in the direction of the rich cluster ABCG85. This catalogue includes previously published redshifts by Beers et al. (1991AJ....102.1581B) and Malumuth et al. (1992AJ....104..495M), together with our 367 new measurements. A total of 305 galaxies have velocities in the interval 13350-20000km/s, and will be considered as members of the cluster. ABCG 85 therefore becomes one of the clusters with the highest number of measured redshifts; its optical properties are being investigated in a companion paper.
- ID:
- ivo://CDS.VizieR/J/A+A/641/A90
- Title:
- AB Dor A VLBI images
- Short Name:
- J/A+A/641/A90
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The fast rotator, pre-main sequence star AB Dor A is a strong and persistent radio emitter. The extraordinary coronal flaring activity is thought to be the origin of compact radio emission and other associated phenomena, such as large slingshot prominences. We aim to investigate the radio emission mechanism and the milliarcsecond radio structure around AB Dor A. We performed phase-referenced VLBI observations at 22.3GHz, 8.4GHz, and 1.4GHz over more than one decade using the Australian VLBI array. Our 8.4GHz images show a double core-halo morphology, similar at all epochs, with emission extending at heights between 5 and 18 stellar radii. Furthermore, the sequence of the 8.4GHz maps shows a clear variation of the source structure within the observing time. However, images at 1.4GHz and 22.3GHz are compatible with a compact source. The phase-reference position at 8.4GHz and 1.4GHz are coincident with those expected from the well-known milliarcsecond-precise astrometry of this star, meanwhile the 22.3GHz position is 4sigma off the prediction in the north-west direction. The origin of this offset is still unclear. We have considered several models to explain the morphology and evolution of the inner radio structure detected in AB Dor A. These models include emission from the stellar polar caps, a flaring, magnetically-driven loop structure, and the presence of helmet streamers. We also investigated a possible close companion to AB Dor A. Our results confirm the extraordinary coronal magnetic activity of this star, capable of producing compact radio structures at very large heights that have so far only been seen in binary interacting systems.