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481. Ridges in the Dark Energy Survey
ID:
ivo://CDS.VizieR/J/MNRAS/500/859
Title:
Ridges in the Dark Energy Survey
Short Name:
J/MNRAS/500/859
Date:
21 Oct 2021
Publisher:
CDS
Description:
Cosmic voids and their corresponding redshift-aggregated projections of mass densities, known as troughs, play an important role in our attempt to model the large-scale structure of the Universe. Understanding these structures leads to tests comparing the standard model with alternative cosmologies, constraints on the dark energy equation of state, and provides evidence to differentiate among gravitational theories. In this paper, we extend the subspace-constrained mean shift algorithm, a recently introduced method to estimate density ridges, and apply it to 2D weak-lensing mass density maps from the Dark Energy Survey Y1 data release to identify curvilinear filamentary structures. We compare the obtained ridges with previous approaches to extract trough structure in the same data, and apply curvelets as an alternative wavelet-based method to constrain densities. We then invoke the Wasserstein distance between noisy and noiseless simulations to validate the denoising capabilities of our method. Our results demonstrate the viability of ridge estimation as a precursor for denoising weak lensing quantities to recover the large-scale structure, paving the way for a more versatile and effective search for troughs.
482. Robust detection of CID double stars in SDSS
ID:
ivo://CDS.VizieR/J/A+A/591/A96
Title:
Robust detection of CID double stars in SDSS
Short Name:
J/A+A/591/A96
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Sloan Digital Sky Survey (SDSS) offers a unique possibility of not only detecting colour induced displacement (CID) double stars but also confirming these detections. Successive cuts are applied to the SDSS data release (DR) 12 database to reduce the size of the sample under consideration. The resulting dataset is then screened with a criterion based on the distance and orientation of the photocentres in different photometric bands. About 3200 distinct objects are classified as CID double stars, 40 of which are confirmed with at least a second detection. A consistency check further validates these detections.
483. ~17000 runaways stars from the Orion Nebula Cluster
ID:
ivo://CDS.VizieR/J/ApJ/900/14
Title:
~17000 runaways stars from the Orion Nebula Cluster
Short Name:
J/ApJ/900/14
Date:
14 Mar 2022 08:53:06
Publisher:
CDS
Description:
We use Gaia DR2 to hunt for runaway stars from the Orion Nebula Cluster (ONC). We search a region extending 45{deg} around the ONC and out to 1 kpc to find sources that have overlapped in angular position with the cluster in the last ~10Myr. We find ~17000 runaway/walkaway candidates that satisfy this 2D traceback condition. Most of these are expected to be contaminants, e.g., caused by Galactic streaming motions of stars at different distances. We thus examine six further tests to help identify real runaways, namely: (1) possessing young stellar object (YSO) colors and magnitudes based on Gaia optical photometry; (2) having IR excess consistent with YSOs based on 2MASS and Wide-field Infrared Survey Explorer photometry; (3) having a high degree of optical variability; (4) having closest approach distances well-constrained to within the cluster half-mass radius; (5) having ejection directions that avoid the main Galactic streaming contamination zone; and (6) having a required radial velocity (RV) for 3D overlap of reasonable magnitude (or, for the 7% of candidates with measured RVs, satisfying 3D traceback). Thirteen sources, not previously noted as Orion members, pass all these tests, while another twelve are similarly promising, except they are in the main Galactic streaming contamination zone. Among these 25 ejection candidates, ten with measured RVs pass the most restrictive 3D traceback condition. We present full lists of runaway/walkaway candidates, estimate the high-velocity population ejected from the ONC, and discuss its implications for cluster formation theories via comparison with numerical simulations.
484. Runaway stars in the 30 Doradus region of the LMC
ID:
ivo://CDS.VizieR/J/AJ/156/98
Title:
Runaway stars in the 30 Doradus region of the LMC
Short Name:
J/AJ/156/98
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a catalog of relative proper motions for 368787 stars in the 30 Doradus region of the Large Magellanic Cloud (LMC), based on a dedicated two-epoch survey with the Hubble Space Telescope and supplemented with proper motions from our pilot archival study. We demonstrate that a relatively short epoch difference of three years is sufficient to reach a level of precision of ~0.1 mas/yr or better. A number of stars with relative proper motions exceeding a 3{sigma} error threshold represent a mixture of Milky Way denizens and 18 potential LMC runaway stars. Based upon 183 VFTS OB stars with the best proper motions, we conclude that none of them moves faster than ~0.3 mas/yr in each coordinate-equivalent to ~70 km/s. Among the remaining 351 VFTS stars with less accurate proper motions, only one candidate OB runaway can be identified. We rule out any OB star in our sample moving at a tangential velocity exceeding ~120 km/s. The most significant result of this study is finding 10 stars over a wide range of masses that appear to have been ejected from the massive star cluster R136 in the tangential plane to angular distances from 35" out to 407", equivalent to 8-98 pc. The tangential velocities of these runaways appear to be correlated with apparent magnitude, indicating a possible dependence on the stellar mass. Lastly, a comparison to proper motions from Gaia DR 2 shows that for several relatively bright stars the DR 2 has an unexpected scatter that cannot be accounted for by the formal errors.
485. Ruprecht 147 DANCe. I.
ID:
ivo://CDS.VizieR/J/A+A/625/A115
Title:
Ruprecht 147 DANCe. I.
Short Name:
J/A+A/625/A115
Date:
21 Oct 2021
Publisher:
CDS
Description:
Ruprecht 147 is the oldest (2.5Gyr) open cluster in the solar vicinity (<300pc), making it an important target for stellar evolution studies and exoplanet searches. We aim to derive a census of members and the luminosity, mass, and spatial distributions of the cluster. We used an astro-photometric data set including all available information from the literature together with our own observations. We processed the data with an updated version of an existent membership selection methodology. We identify 259 high-probability candidate members, including 58 previously unreported. All these candidates cover the luminosity interval between G>6mag to i<21mag. The cluster luminosity and mass distributions are derived with an unprecedented level of details allowing us to recognize, among other features, the Wielen dip. The mass distribution in the low-mass regime drops sharply at 0.4M_{sun}_ even though our data are sensitive to stellar masses down to 0.1M_{sun}_, suggesting that most very-low-mass members left the cluster as the result of its dynamical evolution. In addition, the cluster is highly elongated (ellipticity~0.5) towards the galactic plane, and mass segregated. Our combined Gaia+DANCe data set allows us to obtain an extended list of cluster candidate members, and to derive luminosity, mass, and projected spatial distributions in the oldest open cluster of the solar vicinity.
486. RVel & Hipparcos positions of epsilon Eridani
ID:
ivo://CDS.VizieR/J/AJ/162/181
Title:
RVel & Hipparcos positions of epsilon Eridani
Short Name:
J/AJ/162/181
Date:
14 Mar 2022 06:39:08
Publisher:
CDS
Description:
{epsilon}Eridani is a young planetary system hosting a complex multibelt debris disk and a confirmed Jupiter-like planet orbiting at 3.48au from its host star. Its age and architecture are thus reminiscent of the early Solar System. The most recent study of Mawet et al., which combined radial-velocity data and Ms-band direct imaging upper limits, started to constrain the planet's orbital parameters and mass, but are still affected by large error bars and degeneracies. Here we make use of the most recent data compilation from three different techniques to further refine {epsilon}Eridani b's properties: RVs, absolute astrometry measurements from the Hipparcos and Gaia missions, and new Keck/NIRC2 Ms-band vortex coronagraph images. We combine this data in a Bayesian framework. We find a new mass, M_b_=0.66_-0.09_^+0.12^M_Jup_, and inclination, i=78.81_-22.41_^+29.34^deg, with at least a factor 2 of improvement over previous uncertainties. We also report updated constraints on the longitude of the ascending node, the argument of the periastron, and the time of periastron passage. With these updated parameters, we can better predict the position of the planet at any past and future epoch, which can greatly help define the strategy and planning of future observations and with subsequent data analysis. In particular, these results can assist the search for a direct detection with JWST and the Nancy Grace Roman Space Telescope's coronagraph instrument.
487. RV measurements of eight spectroscopic binaries
ID:
ivo://CDS.VizieR/J/AN/338/671
Title:
RV measurements of eight spectroscopic binaries
Short Name:
J/AN/338/671
Date:
21 Oct 2021
Publisher:
CDS
Description:
Since early 2015 a new radial velocity monitoring campaign is going on at the University Observatory Jena. The aim of this project is to obtain current radial velocity measurements of selected single-lined spectroscopic binary systems, to re-determine and/or constrain their orbital solutions.
488. San Fernando AC Zone Data Reduced to ACRS
ID:
ivo://CDS.VizieR/I/222
Title:
San Fernando AC Zone Data Reduced to ACRS
Short Name:
I/222
Date:
21 Oct 2021
Publisher:
CDS
Description:
The U.S. Naval Observatory is in the process of making new reductions of the Astrographic Catalogue (AC) using a modern reference system, the ACRS, which represents the system of the FK5. The data from the San Fernando Zone, whose plates are centered between declinations -3 and -9 degrees (eq. 1900), have been analyzed for scale, rotation, tilt, coma, magnitude equation, radial distortion and distortions introduced by the use of reseaux in the Carte du Ciel program. The result is a positional catalog of over 225,000 stars on eq. J2000.0, epoch of observation. Additionally, all stars have been matched with the Tycho Input Catalog (revised); those numbers have been added for additional identification purposes.
489. Santiago catalogue of 1105 FK5 stars
ID:
ivo://CDS.VizieR/J/A+AS/95/355
Title:
Santiago catalogue of 1105 FK5 stars
Short Name:
J/A+AS/95/355
Date:
21 Oct 2021
Publisher:
CDS
Description:
The positions in right ascension and declination of 1105 FK5 stars, observed with a Meridian Circle during the period 1979 to 1991, are given. The average mean square error of a position, for the whole catalog, is +/-0.009s in right ascension and +/-0.10arcsec in declination. The mean epoch of the catalog is 1983.148.
490. SANTIAGO 91, RA catalogue
ID:
ivo://CDS.VizieR/J/A+AS/109/501
Title:
SANTIAGO 91, RA catalogue
Short Name:
J/A+AS/109/501
Date:
21 Oct 2021
Publisher:
CDS
Description:
The positions in right ascension of 3387 stars belonging to the Santiago 67 Catalogue, observed with the Repsold Meridian Circle at Cerro Calan, National Astronomical Observatory, during the period 1989 to 1994, are given. The average mean square error of a position, for the whole Catalogue, is +/-0.009 s. The mean epoch of the catalogue is 1991.84.

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