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3511. Danks 1, Danks 2, and RCW 79 variables
ID:
ivo://CDS.VizieR/J/A+A/545/A54
Title:
Danks 1, Danks 2, and RCW 79 variables
Short Name:
J/A+A/545/A54
Date:
21 Oct 2021
Publisher:
CDS
Description:
The ESO Public Survey "VISTA Variables in the Via Lactea"' (VVV) provides deep multi-epoch infrared observations for unprecedented 562 sq. degrees of the Galactic bulge, and adjacent regions of the disk. The VVV observations will foster the construction of a sample of Galactic star clusters with reliable and homogeneously derived physical parameters (e.g., age, distance, and mass, etc.). In this first paper in a series, the methodology employed to establish cluster parameters for the envisioned database are elaborated upon by analysing four known young open clusters: Danks1, Danks2, RCW79, and DBS132. The analysis offers a first glimpse of the information that can be gleaned from the VVV observations for clusters in the final database. Wide-field, deep JHK_s_ VVV observations, combined with new infrared spectroscopy, are employed to constrain fundamental parameters for a subset of clusters. Results are inferred from VVV near-infrared photometry and numerous low resolution spectra (typically more than 10 per cluster). The high quality of the spectra and the deep wide-field VVV photometry enables us to precisely and independently determine the characteristics of the clusters studied, which we compare to previous determinations. An anomalous reddening law in the direction of the Danks clusters is found, specifically E(J-H)/E(H-Ks)=2.20+/-0.06, which exceeds published values for the inner Galaxy. The G305 star forming complex, which includes the Danks clusters, lies beyond the Sagittarius-Carina spiral arm and occupies the Centaurus arm. Finally, the first deep infrared colour-magnitude diagram of RCW79 is presented, which reveals a sizeable pre-main sequence population. A list of candidate variable stars in G305 region is reported. This study demonstrates the strength of the dataset and methodology employed, and constitutes the first step of a broader study which shall include reliable parameters for a sizeable number of poorly characterised and/or newly discovered clusters.
3512. DAO Science Archive observations
ID:
ivo://CDS.VizieR/B/dao
Title:
DAO Science Archive observations
Short Name:
B/dao
Date:
21 Oct 2021
Publisher:
CDS
Description:
The DAO archives are operated by the Canadian Astronomy Data Centre (CADC). These consist of two separate collections: the DAO Science Archive and the DAO Spectroscopic Plate Archive. The DAO Science Archive consists of modern electronic data obtained with the DAO's 1.8-m Plaskett telescope as well as the 1.2-m telescope and McKellar spectrograph. This collection is updated on a daily basis with new data and, as time permits, archival CCD data are also being added. The DAO spectroscopic plate collection in its entirety consists of over 16,800 high-dispersion spectrograms exposed at the coude focus of the 1.2-m DAO telescope and McKellar spectrograph between 1962 and 2000, and more than 93,000 secured at the Cassegrain focus of the DAO 1.8-m telescope and spectrograph between 1918 and 1984. The very great majority of those plates is now in the NRC-Herzberg plate archive. Since a programme to digitize them with the modified in-house PDS has only recently commenced (and with limited resources) there is currently a rather modest number of digital files available for download. However, if you have questions about the availability of plates of a target of particular interest you can we encourage you to contact Elizabeth Griffin or David Bohlender at NRC-Herzberg (elizabeth.griffin@nrc-cnrc.gc.ca), david.bohlender@nrc-cnrc.gc.ca) so that we can search the collection for plates that may be of interest to your research. Both archives allow searches by important criteria such as object name, date, and wavelength and presents the results of the search in a tabular format. The CADC's Data Retrieval facility allows archive users to download archival data directly to their own computers. Proprietary data can also be retrieved, but only by the Principal Investigator (PI) of the science program in question and any colleagues the PI has granted access to that program's data. These users must also register with the CADC in order to enable authorization tests to be made before such proprietary data is accessed. The proprietary period for DAO pixel data is 12 months from the time of the observation. Metadata associated with the pixel data (i.e. the FITS header) is public immediately. Because of uncertainties in the absolute pointing accuracy of the DAO telescopes, it is recommended that a relatively large search radius (e.g. 5') be used in any DAO archive searches for specific targets.
3513. Dark clouds imaging polarimetry
ID:
ivo://CDS.VizieR/J/A+AS/141/175
Title:
Dark clouds imaging polarimetry
Short Name:
J/A+AS/141/175
Date:
21 Oct 2021
Publisher:
CDS
Description:
A set of eight Bok Globules CB3, CB25, CB39, CB52, CB54, CB58, CB62 and CB246 were observed polarimetrically in white light, using our Imaging Polarimater (IMPOL), from the 1.2m IR telescope at Mount Abu, India. The observations were carried out on different nights during the period December 1997 and April 1998. The CCD images obtained from the instrument (IMPOL) were analyzed, to produce polarization map of the Bok Globules. The stars in the field, which are mostly background to the cloud show typically 2% linear polarization. Clouds which are less dynamic (having ^12^CO line widths {Delta}V<2.5km/s) in general show slightly better alignment of polarization vectors with the projected direction of galactic plane. On the other hand, the more dynamic group of clouds has polarization vectors more scattered and poorly aligned with the projected direction of the galactic plane. However one of the clouds observed, CB58, does not follow this trend very well.
3514. Dark matter annihilation in galaxy clusters
ID:
ivo://CDS.VizieR/J/MNRAS/425/477
Title:
Dark matter annihilation in galaxy clusters
Short Name:
J/MNRAS/425/477
Date:
21 Oct 2021
Publisher:
CDS
Description:
Clusters of galaxies are potentially important targets for indirect searches for dark matter (DM) annihilation. Here we reassess the detection prospects for annihilation in massive haloes, based on a statistical investigation of 1743 clusters in the new Meta-Catalogue of X-ray Clusters (MCXC). We derive a new limit for the extragalactic DM annihilation background of at least 20 per cent of that originating from the Galaxy for an integration angle of 0.1{deg}.
3515. Dark matter halo models for SPARC galaxies
ID:
ivo://CDS.VizieR/J/ApJS/247/31
Title:
Dark matter halo models for SPARC galaxies
Short Name:
J/ApJS/247/31
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present rotation curve fits to 175 late-type galaxies from the Spitzer Photometry and Accurate Rotation Curves database using seven dark matter (DM) halo profiles: pseudo-isothermal, Burkert, Navarro-Frenk-White (NFW), Einasto, Di Cintio+ (DC14; 2014MNRAS.441.2986D), cored-NFW, and a new semi-empirical profile named Lucky13. We marginalize over the stellar mass-to-light ratio, galaxy distance, disk inclination, halo concentration, and halo mass (and an additional shape parameter for Einasto) using a Markov Chain Monte Carlo method. We find that cored halo models, such as the DC14 and Burkert profiles, generally provide better fits to rotation curves than the cuspy NFW profile. The stellar mass-halo mass relation from abundance matching is recovered by all halo profiles once imposed as a Bayesian prior, whereas the halo mass-concentration relation is not reproduced in detail by any halo model.
3516. Dark matter profiles in dwarf galaxies
ID:
ivo://CDS.VizieR/J/ApJ/801/74
Title:
Dark matter profiles in dwarf galaxies
Short Name:
J/ApJ/801/74
Date:
21 Oct 2021
Publisher:
CDS
Description:
Gamma-ray searches for dark matter annihilation and decay in dwarf galaxies rely on an understanding of the dark matter density profiles of these systems. Conversely, uncertainties in these density profiles propagate into the derived particle physics limits as systematic errors. In this paper we quantify the expected dark matter signal from 20 Milky Way dwarfs using a uniform analysis of the most recent stellar-kinematic data available. Assuming that the observed stellar populations are equilibrium tracers of spherically symmetric gravitational potentials that are dominated by dark matter, we find that current stellar-kinematic data can predict the amplitudes of annihilation signals to within a factor of a few for the ultra-faint dwarfs of greatest interest. On the other hand, the expected signal from several classical dwarfs (with high-quality observations of large numbers of member stars) can be localized to the ~20% level. These results are important for designing maximally sensitive searches in current and future experiments using space and ground-based instruments.
3517. Dark molecular gas in the Galaxy II. Perseus arm
ID:
ivo://CDS.VizieR/J/ApJ/883/158
Title:
Dark molecular gas in the Galaxy II. Perseus arm
Short Name:
J/ApJ/883/158
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report the results from a new, highly sensitive ({Delta}T_mb_~3mK) survey for thermal OH emission at 1665 and 1667MHz over a dense, 9x9pix grid covering a 1{deg}x1{deg} patch of sky in the direction of l=105.00{deg}, b=+2.50{deg} toward the Perseus spiral arm of our Galaxy. We compare our Green Bank Telescope 1667MHz OH results with archival ^12^CO(1-0) observations from the Five College Radio Astronomy Observatory Outer Galaxy Survey within the velocity range of the Perseus Arm at these galactic coordinates. Out of the 81 statistically independent pointings in our survey area, 86% show detectable OH emission at 1667MHz, and 19% of them show detectable CO emission. We explore the possible physical conditions of the observed features using a set of diffuse molecular cloud models. In the context of these models, both OH and CO disappear at current sensitivity limits below an A_v_ of 0.2, but the CO emission does not appear until the volume density exceeds 100-200cm^-3^. These results demonstrate that a combination of low column density A_v_ and low volume density n_H_ can explain the lack of CO emission along sight lines exhibiting OH emission. The 18cm OH main lines, with their low critical density of n*~1cm^-3^, are collisionally excited over a large fraction of the quiescent galactic environment and, for observations of sufficient sensitivity, provide an optically thin radio tracer for diffuse H_2_.
3518. Dark Nebulae and Globules for l=240-360deg
ID:
ivo://CDS.VizieR/VII/68A
Title:
Dark Nebulae and Globules for l=240-360deg
Short Name:
VII/68A
Date:
21 Oct 2021
Publisher:
CDS
Description:
(adapted from Anne C. Raugh, NASA STI-T-1-5810-508-86) The catalog is a compilation of data gleened from a study of the European Southern Observatory Quick Blue Survey (ESO(b)) and SRC-J Sky Atlas on 489 dark clouds and 331 globules. The data compiled include position, size, opacity and morphological classification (in the system of van den Bergh, 1972). Also included is a FITS file containing a 500x1400 pixel map of the survey area.
3519. Data and parameters for subgiant sample
ID:
ivo://CDS.VizieR/J/ApJ/915/19
Title:
Data and parameters for subgiant sample
Short Name:
J/ApJ/915/19
Date:
02 Feb 2022 06:48:11
Publisher:
CDS
Description:
Given their location on the Hertzsprung-Russell (H-R) diagram, thoroughly characterized subgiant stars can place stringent constraints on a wide range of astrophysical problems. Accordingly, they are prime asteroseismic targets for the Transiting Exoplanet Survey Satellite (TESS) mission. In this work, we infer stellar properties for a sample of 347 subgiants located in the TESS Continuous Viewing Zones, which we select based on their likelihood of showing asteroseismic oscillations. We investigate how well they can be characterized using classical constraints (photometry, astrometry) and validate our results using spectroscopic values. We derive luminosities, effective temperatures, and radii with mean 1{sigma} random (systematic) uncertainties of 4.5% (2%), 33K (60K), and 2.2% (2%), as well as more model-dependent quantities such as surface gravities, masses, and ages. We use our sample to demonstrate that subgiants are ideal targets for mass and age determination based on H-R diagram location alone, discuss the advantages of stellar parameters derived from a detailed characterization over widely available catalogs, show that the generally used 3D extinction maps tend to overestimate the extinction for nearby stars (distance <=500pc), and find a correlation that supports the rotation-activity connection in post-main-sequence stars. The complementary roles played by classical and asteroseismic data sets will open a window to unprecedented astrophysical studies using subgiant stars.
3520. Database of circumstellar OH masers
ID:
ivo://CDS.VizieR/J/A+A/582/A68
Title:
Database of circumstellar OH masers
Short Name:
J/A+A/582/A68
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a new database of circumstellar OH masers at 1612, 1665, and 1667MHz in the Milky Way galaxy. The database (version 2.4) contains 13655 observations and 2341 different stars detected in at least one transition. Detections at 1612MHz are considered to be complete until the end of 2014 as long as they were published in refereed papers. Detections of the main lines (1665 and 1667MHz) and non-detections in all transitions are included only if published after 1983. The database contains flux densities and velocities of the two strongest maser peaks, the expansion velocity of the shell, and the radial velocity of the star. Links are provided for about 100 stars (<5% of all stars with OH masers) to interferometric observations and monitoring programs of the maser emission published since their beginnings in the 1970s. Access to the database is possible over the Web (www.hs.uni-hamburg.de/maserdb), allowing cone searches for individual sources and lists of sources. A general search is possible in selected regions of the sky and by defining ranges of flux densities and/or velocities. Alternative ways to access the data are via the German Virtual Observatory and the CDS.

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