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531. Adopting the UAT as an IVOA vocabulary
ID:
ivo://ivoa.net/std/uat-as-upstream
Title:
Adopting the UAT as an IVOA vocabulary
Short Name:
uat-as-upstream
Date:
25 Jul 2022 13:00:00
Publisher:
IVOA
Description:
The Unified Astronomy Thesaurus (UAT) provides a comprehensive, interlinked set of concepts relevant for astronomy and astrophysics using SKOS. It is taken up in the Virtual Observatory at least for registry subject keywords. For various reasons, it is desirable to have the UAT available subject to the constraints laid down in the IVOA Vocabularies in the VO 2 specification. This Note describes the rationale and the details of the UAT adoption by the IVOA.
532. ADS 9731: a new sextuple system
ID:
ivo://CDS.VizieR/J/PAZh/24/918
Title:
ADS 9731: a new sextuple system
Short Name:
J/PAZh/24/918
Date:
21 Oct 2021
Publisher:
CDS
Description:
Observations with the correlation radial velocity meter of ADS 9731 were carried out during 1996-1997. We established that the components A and D of the visual quadruple system ADS 9731 are spectroscopic binaries with periods of 3.87 and 14.3 days, respectively. Their orbits are computed. New photometry has demonstrated the absence of eclipses in the close pair Aab. The spectral types and luminosities of all six components matching the are found.
533. ADS 11061 radial velocities
ID:
ivo://CDS.VizieR/J/A+A/409/245
Title:
ADS 11061 radial velocities
Short Name:
J/A+A/409/245
Date:
21 Oct 2021
Publisher:
CDS
Description:
The evolutionary status and origin of the most eccentric known binary in a quadruple system, 41 Dra (e=0.9754, period 3.413yr), are discussed. New observations include the much improved combined speckle-interferometric orbit, resolved photometry of the components and their spectroscopic analysis. The age of the system is 2.5+/-0.2Gyr; all four components are likely coeval. The high eccentricity of the orbit together with known age and masses provide a constraint on the tidal circularization theory: it seems that the eccentric orbit survived because the convective zones of the F-type dwarfs were very thin. Now as the components of 41 Dra are leaving the Main Sequence, their increased interaction at each periastron passage may result in detectable changes in period and eccentricity.
534. A dust model for bet Pic from 0.58 to 870um
ID:
ivo://CDS.VizieR/J/ApJ/823/108
Title:
A dust model for bet Pic from 0.58 to 870um
Short Name:
J/ApJ/823/108
Date:
21 Oct 2021
Publisher:
CDS
Description:
We investigate whether varying the dust composition (described by the optical constants) can solve a persistent problem in debris disk modeling --the inability to fit the thermal emission without overpredicting the scattered light. We model five images of the {beta} Pictoris disk: two in scattered light from the Hubble Space Telescope (HST)/Space Telescope Imaging Spectrograph at 0.58{mu}m and HST/Wide Field Camera 3 (WFC3) at 1.16{mu}m, and three in thermal emission from Spitzer/Multiband Imaging Photometer for Spitzer (MIPS) at 24{mu}m, Herschel/PACS at 70{mu}m, and Atacama Large Millimeter/submillimeter Array at 870{mu}m. The WFC3 and MIPS data are published here for the first time. We focus our modeling on the outer part of this disk, consisting of a parent body ring and a halo of small grains. First, we confirm that a model using astronomical silicates cannot simultaneously fit the thermal and scattered light data. Next, we use a simple generic function for the optical constants to show that varying the dust composition can improve the fit substantially. Finally, we model the dust as a mixture of the most plausible debris constituents: astronomical silicates, water ice, organic refractory material, and vacuum. We achieve a good fit to all data sets with grains composed predominantly of silicates and organics, while ice and vacuum are, at most, present in small amounts. This composition is similar to one derived from previous work on the HR 4796A disk. Our model also fits the thermal spectral energy distribution, scattered light colors, and high-resolution mid-IR data from T-ReCS for this disk. Additionally, we show that sub-blowout grains are a necessary component of the halo.
535. Advanced Camera for Surveys
ID:
ivo://archive.stsci.edu/hst/acs
Title:
Advanced Camera for Surveys
Short Name:
HST.ACS
Date:
23 Jul 2020 19:47:47
Publisher:
Space Telescope Science Institute Archive
Description:
HST Advanced Camera for Surveys (ACS) - Images: CCD images between 3,700 - 11
536. Advanced Usage of HiPS and MOCs
ID:
ivo://edu.euro-vo.org/extern/hipsmoc
Title:
Advanced Usage of HiPS and MOCs
Date:
27 Dec 2024 08:31:05
Publisher:
The GAVO DC team
Description:
This course introduces advanced usage of Hierarchical Progressive Surveys (HiPS) and Multi-Order Coverage (MOC) maps in Aladin. Using this document, you will learn how to handle a problem like : “I have a set of images. I would like to select regions in my observations that are above a given threshold in another survey (e.g. at low extinction), retrieve objects from very large catalogs (e.g. Gaia + WISE) in these non-trivial shapes and not-necessarily-connected regions, and combine them to visualise some quantities (e.g. color color diagram).“
537. A 3D view of the Hyades population
ID:
ivo://CDS.VizieR/J/A+A/623/A35
Title:
A 3D view of the Hyades population
Short Name:
J/A+A/623/A35
Date:
21 Oct 2021
Publisher:
CDS
Description:
Our scientific goal is to provide a 3D map of the nearest open cluster to the Sun, the Hyades, combining the recent release of Gaia astrometric data, ground-based parallaxes of sub-stellar member candidates and photometric data from surveys which cover large areas of the cluster. We combined the second Gaia release with ground-based H-band parallaxes obtained with the infrared camera on the 2-m robotic Liverpool telescope to astrometrically identify stellar and sub-stellar members of the Hyades, the nearest open cluster to the Sun. We find 1764 objects within 70 degree radius from the cluster center from the Gaia second data release, whose kinematic properties are consistent with the Hyades. We limit our study to 30pc from the cluster center (47.03+/-0.20pc) where we identify 710 candidate members, including 85 and 385 in the core and tidal radius, respectively. We determine proper motions and parallaxes of eight candidate brown dwarf members and confirm their membership. Using the 3D positions and a model-based mass-luminosity relation we derive a luminosity and mass function in the 0.04 to 2.5M_{sun}_ range. We confirm evidence for mass segregation in the Hyades and find a dearth of brown dwarfs in the core of the cluster. From the white dwarf members we estimate an age of 640^+67^_-49_Myr. We identify a list of members in the Hyades cluster from the most massive stars down to the brown dwarfs. We produce for the first time a 3D map of the Hyades cluster in the stellar and sub-stellar regimes and make available the list of candidate members.
538. A 3D Voronoi+Gapper galaxy cluster finder. II.
ID:
ivo://CDS.VizieR/J/ApJ/869/145
Title:
A 3D Voronoi+Gapper galaxy cluster finder. II.
Short Name:
J/ApJ/869/145
Date:
21 Oct 2021
Publisher:
CDS
Description:
We identify 1901 galaxy clusters (N_g_>=2) with the gapping-filtering in radial velocity (VoML+G) algorithm (Paper I; Campusano+ 2017ApJ...838..109P) on the two-Degree Field Galaxy Redshift Survey (2dFGRS). We present the 341 clusters with at least 10 galaxies that are within 0.009<z<0.14 (the Catalog), of which 254 (~75%) have counterparts in the literature (NED), with the remainder (87) plausibly "new" because of incompleteness of previous searches or unusual galaxy contents. The 207 clusters within z=0.04--0.09 are used to study the properties of the galaxy systems in the nearby universe, including their galaxy contents parameterized by the late-type galaxy fractions (f_L_). For this nearly complete cluster subsample, we find the following: (i) 63% are dominated by early-type galaxies (i.e., the late-type-poor clusters, f_L_<0.5) with corresponding mean multiplicity and logarithmic virial mass (in units of M_{sun}_) of 22+/-1 and 12.91+/-0.04, respectively; and (ii) 37% are dominated by late-type galaxies (i.e., the late-type-rich clusters, f_L_>=0.5) with corresponding mean multiplicity and logarithmic virial mass (in units of M_{sun}_) of 15.7+/-0.9 and 12.66+/-0.07, respectively. The statistical analysis of the late-type fraction distribution supports, with a 3{sigma} confidence level, the presence of two population components. It is suggested that the late-type-poor galaxy systems reflect and extend the class of Abell-APM-EDCC clusters and that the late-type-rich systems (~one-third of the total) belong to a new, previously unappreciated class. The late-type-rich clusters, on average high mass-to-light ratio systems, appear to be more clustered on large scales than the late-type-poor clusters. A class of late-type-rich clusters is not predicted by current theory.
539. AE Aur and iota Ori runaway stars RV curves
ID:
ivo://CDS.VizieR/J/AN/341/645
Title:
AE Aur and iota Ori runaway stars RV curves
Short Name:
J/AN/341/645
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of our spectroscopic monitoring observations of the late O-type runaway stars AE Aur and iota Ori, carried out between September 2016 and May 2018 using the Echelle spectrograph FLECHAS at the University Observatory Jena. For both stars, we obtained current radial velocity (RV) measurements with better precision than before. These results can be used for further advanced calculations of their space motion, needed to determine, for example, their place of origin in our Galaxy. In this paper, we describe the observations and the data reduction, as well as the analysis of all spectral data. We find a stable RV for AE Aur and confirm iota Ori as a double-lined spectroscopic binary and derive its current Keplerian orbital elements.
540. Ae/Be stars of Magellanic Bridge in JHKs
ID:
ivo://CDS.VizieR/J/ApJ/658/358
Title:
Ae/Be stars of Magellanic Bridge in JHKs
Short Name:
J/ApJ/658/358
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have found Herbig Ae/Be star candidates in the western region of the Magellanic Bridge. Using the near-infrared camera SIRIUS and the 1.4m telescope IRSF, we surveyed ~3.0{deg}x1.3{deg} (24{deg}<~RA<~36{deg}, -75.0{deg}<~DE<~-73.7{deg}) in the J, H, and Ks bands. On the basis of colors and magnitudes, about 200 Herbig Ae/Be star candidates are selected. Considering the contaminations by miscellaneous sources, such as foreground stars and early-type dwarfs in the Magellanic Bridge, we estimate that about 80 (#40%) of the candidates are likely to be Herbig Ae/Be stars. We also found one concentration of the candidates at the young star cluster NGC 796, strongly suggesting the existence of pre-main-sequence (PMS) stars in the Magellanic Bridge. This is the first detection of PMS star candidates in the Magellanic Bridge, and if they are genuine PMS stars, this could be direct evidence of recent star formation. However, the estimate of the number of Herbig Ae/Be stars depends on the fraction of classical Be stars, and thus a more precise determination of the Be star fraction or observations to differentiate between the Herbig Ae/Be stars and classical Be stars are required.

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