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1161. New lens candidates in CFHTLS
ID:
ivo://CDS.VizieR/J/A+A/592/A75
Title:
New lens candidates in CFHTLS
Short Name:
J/A+A/592/A75
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of a new search for galaxy-scale strong lensing systems in CFHTLS Wide. Our lens-finding technique involves a preselection of potential lens galaxies, applying simple cuts in size and magnitude. We then perform a Principal Component Analysis of the galaxy images, ensuring a clean removal of the light profile. Lensed features are searched for in the residual images using the clustering topometric algorithm DBSCAN. We find 1098 lens candidates that we inspect visually, leading to a cleaned sample of 109 new lens candidates. Using realistic image simulations we estimate the completeness of our sample and show that it is independent of source surface brightness, Einstein ring size (image separation) or lens redshift. We compare the properties of our sample to previous lens searches in CFHTLS. Including the present search, the total number of lenses found in CFHTLS amounts to 678, which corresponds to ~4 lenses per square degree down to i(AB)=24.8. This is equivalent to ~60.000 lenses in total in a survey as wide as Euclid, but at the CFHTLS resolution and depth.
1162. New Northern common proper-motion pairs
ID:
ivo://CDS.VizieR/J/MNRAS/355/585
Title:
New Northern common proper-motion pairs
Short Name:
J/MNRAS/355/585
Date:
21 Oct 2021
Publisher:
CDS
Description:
A list of 705 new Northern Celestial Hemisphere common proper motion pairs between 18 hours and 6 hours Right Ascension and 0 degrees and roughly 45 degrees Declination as derived from the Second U.S. Naval Observatory CCD Astrograph Catalog is presented, along with details of separation, motion, brightness and colour. This list is supplemented by a further 267 such pairs, derived in exactly the same way as the above 705 within the same Declination range, but for the region between 6 hours and 18 hours Right Ascension that was not included in the printed paper.
1163. 570 new open clusters in the Galactic disc
ID:
ivo://CDS.VizieR/J/A+A/635/A45
Title:
570 new open clusters in the Galactic disc
Short Name:
J/A+A/635/A45
Date:
21 Oct 2021
Publisher:
CDS
Description:
Open clusters are key targets for studies of Galaxy structure and evolution, and stellar physics. Since the Gaia data release 2 (DR2), the discovery of undetected clusters has shown that previous surveys were incomplete. Our aim is to exploit the Big Data capabilities of machine learning to detect new open clusters in Gaia DR2, and to complete the open cluster sample to enable further studies of the Galactic disc. We use a machine-learning based methodology to systematically search the Galactic disc for overdensities in the astrometric space and identify the open clusters using photometric information. First, we used an unsupervised clustering algorithm, DBSCAN, to blindly search for these overdensities in Gaia DR2 (l, b, varpi, mu_alpha_*, mu_delta_), then we used a deep learning artificial neural network trained on colour-magnitude diagrams to identify isochrone patterns in these overdensities, and to confirm them as open clusters. We find 570 new open clusters distributed along the Galactic disc in the region |b|<20{deg}. We detect substructure in complex regions, and identify the tidal tails of a disrupting cluster UBC 274 of ~3Gyr located at ~2kpc. Adapting the mentioned methodology to a Big Data environment allows us to target the search using the physical properties of open clusters instead of being driven by computational limitations. This blind search for open clusters in the Galactic disc increases the number of known open clusters by 45%.
1164. New Ori OB1 members
ID:
ivo://CDS.VizieR/J/AJ/129/907
Title:
New Ori OB1 members
Short Name:
J/AJ/129/907
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present results of a large-scale, multi-epoch optical survey of the Orion OB1 association, carried out with the QUEST camera at the Venezuela National Astronomical Observatory (CIDA). We identify for the first time the widely spread low-mass, young population in the Ori OB1a and OB1b subassociations. Candidate members were picked up by their variability in the V band and position in color-magnitude diagrams. We obtained spectra to confirm membership. In a region spanning ~68{deg}^2^, we found 197 new young stars; of these, 56 are located in the Ori OB1a subassociation and 141 in Ori OB1b.
1165. New point sources in the WMAP 7yr data
ID:
ivo://CDS.VizieR/J/ApJ/753/27
Title:
New point sources in the WMAP 7yr data
Short Name:
J/ApJ/753/27
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have developed a new needlet-based method to detect point sources in cosmic microwave background (CMB) maps and have applied it to the Wilkinson Microwave Anisotropy Probe (WMAP) 7 year data. We use both the individual frequency channels as well as internal templates, the latter being the difference between pairs of frequency channels and hence having the advantage that the CMB component is eliminated. Using the area of the sky outside the Kq85 galactic mask, we detect a total of 2102 point sources at the 5{sigma} level in either the frequency maps or the internal templates. Of these, 1116 are detected either at 5{sigma} directly in the frequency channels or at 5{sigma} in the internal templates and >=3{sigma} at the corresponding position in the frequency channels. Of the 1116 sources, 603 are detections that have not been reported so far in WMAP data. We have made a catalog of these sources available with position and flux estimated in the WMAP channels where they are seen. In total, we identified 1029 of the 1116 sources with counterparts at 5GHz and 69 at other frequencies.
1166. NEWPS_5{sigma}_ source catalogue from WMAP
ID:
ivo://CDS.VizieR/J/ApJS/170/108
Title:
NEWPS_5{sigma}_ source catalogue from WMAP
Short Name:
J/ApJS/170/108
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have used the MHW2 filter to obtain estimates of the flux densities at the WMAP frequencies of a complete sample of 2491 sources, mostly brighter than 500mJy at 5GHz, distributed over the whole sky excluding a strip around the Galactic equator (|b|<=5{deg}). After having detected 933 sources at the >=3{sigma} level in the MHW2 filtered maps-our New Extragalactic WMAP Point Source Catalogue (NEWPS_3{sigma}_)-we are left with 381 sources at >=5{sigma} in at least one WMAP channel, 369 of which constitute our NEWPS_5{sigma}_ catalog. It is remarkable to note that 98 (i.e., 26%) sources detected at are "new," they are not present in the WMAP catalog.
1167. New rotation measures from the CGPS
ID:
ivo://CDS.VizieR/J/ApJS/253/48
Title:
New rotation measures from the CGPS
Short Name:
J/ApJS/253/48
Date:
21 Oct 2021
Publisher:
CDS
Description:
Faraday rotation provides a valuable tracer of magnetic fields in the interstellar medium; catalogs of Faraday rotation measures provide key observations for studies of the Galactic magnetic field. We present a new catalog of rotation measures derived from the Canadian Galactic Plane Survey, covering a large region of the Galactic plane spanning 52{deg}<l<192{deg}, -3{deg}<b<5{deg}, along with northern and southern latitude extensions around l~105{deg}. We have derived rotation measures for 2234 sources (4 of which are known pulsars), 75% of which have no previous measurements, over an area of approximately 1300deg^2^. These new rotation measures increase the measurement density for this region of the Galactic plane by a factor of 2.
1168. NEWS catalog
ID:
ivo://CDS.VizieR/J/A+A/644/A69
Title:
NEWS catalog
Short Name:
J/A+A/644/A69
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a catalogue of candidates in extragalactic objects -- the Northern Extragalactic WISExPan-STARRS (NEWS), which covers almost 3/4 of the sky in a broad optical-infrared spectral range, with a depth of up to 23mag in optical filter g. To create the NEWS catalogue, we used the mid-IR data of the WISE survey (W1,W2) paired up with photometric information of the Pan-STARRS DR1 survey in the optical and near-IR (g,r,i,z,y) spectral ranges. Our catalogue is the result of a classification of the WISExPan-STARRS objects with the SVM machine-learning algorithm. The classification was based solely on photometric information and the automatic creation of features that was carried out using an autoencoder neural network. NEWS catalogue contains 40,350,492 extragalactic objects (galaxies and quasars), identified with a high classification quality (>98%).
1169. New SNe in SDSS DR9
ID:
ivo://CDS.VizieR/J/MNRAS/450/905
Title:
New SNe in SDSS DR9
Short Name:
J/MNRAS/450/905
Date:
21 Oct 2021
Publisher:
CDS
Description:
Using a method to discover and classify supernovae (SNe) in galaxy spectra, we detect 91 Type Ia SNe (SNe Ia) and 16 Type II SNe (SNe II) among ~740000 galaxies of all types and ~215000 star-forming galaxies without active galactic nuclei, respectively, in Data Release 9 of the Sloan Digital Sky Survey. Of these SNe, 15 SNe Ia and eight SNe II are new discoveries reported here for the first time. We use our SN samples to measure SN rates per unit mass as a function of galaxy stellar mass, star-formation rate (SFR), and specific SFR (sSFR), as derived by the MPA-JHU Galspec pipeline. We show that correlations between SN Ia and SN II rates per unit mass and galaxy stellar mass, SFR, and sSFR can be explained by a combination of the respective SN delay-time distributions (the distributions of times that elapse between the formation of a stellar population and all ensuing SNe), the ages of the surveyed galaxies, the redshifts at which they are observed, and their star formation histories.
1170. New standards in 18th century astrometry
ID:
ivo://CDS.VizieR/J/A+A/567/A26
Title:
New standards in 18th century astrometry
Short Name:
J/A+A/567/A26
Date:
21 Oct 2021
Publisher:
CDS
Description:
The present high accuracy of stellar positions and proper motions allows us to determine the positional accuracy of old stellar catalogues. This has already been done for the most important catalogues from before the 18th century. Our aim is to extend this study to several 18th century catalogues. To do this, I studied ten catalogues: those of Flamsteed and Romer, four catalogues of La Caille, and catalogues of Tobias Mayer, Bradley, Piazzi, and Lalande. A comparison with modern data, mostly from Hipparcos, compiled in the Simbad data base of the CDS allowed me to determine the position errors of these catalogues. I also compared the stellar visual magnitudes given in eight of these catalogues with photometric V magnitudes. Thanks to novel instruments, the r.m.s. positional accuracy improved from thousands to hundreds of arc seconds in older catalogues to less than one minute in that of Flamsteed, and to 2-6 arcseconds in the other catalogues I examined. These improvements allowed for the first time relatively accurate proper motions to be determined by 19th century astronomers.