- 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.
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Search Results
- 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}.
- 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.
- 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.
- 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_.
- 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.
- 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.
- 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.
3519. Data Central SCS
- ID:
- ivo://purx/datacentral-scs
- Title:
- Data Central SCS
- Short Name:
- DCSCS
- Date:
- 15 Jun 2021 11:47:41
- Publisher:
- Data Central
- Description:
- Data Central Simple Cone Search. Access Data Central and other catalogues.
- ID:
- ivo://CDS.VizieR/J/A+A/550/A88
- Title:
- Data cubes of NGC 5253 (476-682nm)
- Short Name:
- J/A+A/550/A88
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present Gemini-S/GMOS-IFU optical spectroscopy of four regions near the centre of the nearby (3.8Mpc) dwarf starburst galaxy NGC 5253.