Search

Start Over Subject surveys Result Type text/xml+votable
1201. NEP raster ROSAT X-ray/Optical catalog
ID:
ivo://CDS.VizieR/J/A+A/645/A95
Title:
NEP raster ROSAT X-ray/Optical catalog
Short Name:
J/A+A/645/A95
Date:
21 Oct 2021
Publisher:
CDS
Description:
The North-Ecliptic Pole is an important region for extragalactic surveys. Deep/wide contiguous surveys are being performed by several space observatories. We analyse all ROSAT pointed and survey observations within 40deg^2^ around the NEP, restricting the field-of-view to the inner 30' radius. We obtain an X-ray catalogue of 805 sources with 0.5-2keV fluxes >2.9*10^-15^erg/cm^2^/s, a factor of three deeper than the ROSAT All-Sky Survey in this field. The sensitivity and angular resolution of our data are comparable to the eROSITA All-Sky Survey expectations. The 50% position error radius of the sample of X-ray sources is ~10". We use HEROES optical and near-infrared imaging photometry from Subaru and CFHT telescopes together with literature catalogues and a new deep and wide Spitzer survey in the field to identify X-ray sources and calculate photometric redshifts for the candidate counterparts. In particular we utilize mid-IR colours to identify AGN X-ray counterparts. Despite relatively large error circles and faint counterparts, confusion and systematic errors, we obtain a rather reliable catalogue of 766 optical counterparts, redshifts and optical classifications. We find a new population of luminous absorbed X-ray AGN at large redshifts, not recognized in previous X-ray surveys, but identified in our work due to the unique combination of survey solid angle, X-ray sensitivity and multiwavelength photometry. We also use the WISE and Spitzer photometry to identify a sample of 185 AGN selected purely through mid-IR colours, most of which are not detected by ROSAT. Their redshifts and upper limits to X-ray luminosity and X-ray-to-optical flux ratios are even higher than for the new class of X-ray selected luminous type 2 AGN (AGN2); they are probably a natural extension of this sample. This unique dataset is important as a reference sample for future deep surveys in the NEP region, in particular for eROSITA and also for Euclid and SPHEREX. We predict that most of the absorbed distant AGN should be readily picked up by eROSITA, but they require sensitive mid-IR imaging to be recognized as optical counterparts.
1202. New extreme trans-Neptunian objects
ID:
ivo://CDS.VizieR/J/AJ/152/221
Title:
New extreme trans-Neptunian objects
Short Name:
J/AJ/152/221
Date:
21 Oct 2021
Publisher:
CDS
Description:
We are performing a wide and deep survey for extreme distant solar system objects. Our goal is to understand the high-perihelion objects Sedna and 2012 VP113 and determine if an unknown massive planet exists in the outer solar system. The discovery of new extreme objects from our survey of some 1080 square degrees of sky to over 24th magnitude in the r-band are reported. Two of the new objects, 2014 SR349 and 2013 FT28, are extreme detached trans-Neptunian objects, which have semimajor axes greater than 150 au and perihelia well beyond Neptune (q>40au). Both new objects have orbits with arguments of perihelia within the range of the clustering of this angle seen in the other known extreme objects. One of these objects, 2014 SR349, has a longitude of perihelion similar to the other extreme objects, but 2013 FT28 is about 180{deg} away or anti-aligned in its longitude of perihelion. We also discovered the first outer Oort Cloud object with a perihelion beyond Neptune, 2014 FE72. We discuss these and other interesting objects discovered in our ongoing survey. All the high semimajor axis (a>150au) and high-perihelion (q>35au) bodies follow the previously identified argument of perihelion clustering as first reported and explained as being from an unknown massive planet in 2014 by Trujillo & Sheppard, which some have called Planet X or Planet Nine. With the discovery of 2013 FT28 on the opposite side of the sky, we now report that the argument of perihelion is significantly correlated with the longitude of perihelion and orbit pole angles for extreme objects and find there are two distinct extreme clusterings anti-aligned with each other. This previously unnoticed correlation is further evidence of an unknown massive planet on a distant eccentric inclined orbit, as extreme eccentric objects with perihelia on opposite sides of the sky (180{deg} longitude of perihelion differences) would approach the inclined planet at opposite points in their orbits, thus making the extreme objects prefer to stay away from opposite ecliptic latitudes to avoid the planet (i.e., opposite argument of perihelia or orbit pole angles).
1203. New Fermi/LAT extragalactic sources
ID:
ivo://CDS.VizieR/J/ApJ/742/66
Title:
New Fermi/LAT extragalactic sources
Short Name:
J/ApJ/742/66
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the analysis of 2.1 years of Fermi Large Area Telescope (LAT) data on 491 Seyfert galaxies detected by the Swift Burst Alert Telescope (BAT) survey. Only the two nearest objects, NGC 1068 and NGC 4945, which were identified in the Fermi first year catalog (Abdo et al. 2010, Cat. J/ApJ/715/429), are detected. Using Swift/BAT and radio 20cm fluxes, we define a new radio-loudness parameter R_X,BAT_ where radio-loud objects have logR_X,BAT_> -4.7. Based on this parameter, only radio-loud sources are detected by Fermi/LAT. An upper limit to the flux of the undetected sources is derived to be ~2x10^-11^photons/cm^2^/s, approximately seven times lower than the observed flux of NGC 1068. Assuming a median redshift of 0.031, this implies an upper limit to the {gamma}-ray (1-100GeV) luminosity of <~3x10^41^erg/s. In addition, we identified 120 new Fermi/LAT sources near the Swift/BAT Seyfert galaxies with significant Fermi/LAT detections. A majority of these objects do not have Swift/BAT counterparts, but their possible optical counterparts include blazars, flat-spectrum radio quasars, and quasars.
1204. NEWFIRM MBS: photometric catalogs
ID:
ivo://CDS.VizieR/J/ApJ/735/86
Title:
NEWFIRM MBS: photometric catalogs
Short Name:
J/ApJ/735/86
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present deep near-IR (NIR) medium-bandwidth photometry over the wavelength range 1-1.8um in the All-wavelength Extended Groth strip International Survey (AEGIS) and Cosmic Evolution Survey (COSMOS) fields. The observations were carried out using the NOAO Extremely Wide-Field Infrared Imager (NEWFIRM) on the Mayall 4m Telescope on Kitt Peak as part of the NEWFIRM Medium-Band Survey (NMBS), an NOAO survey program. In this paper, we describe the full details of the observations, data reduction, and photometry for the survey. We also present a public K-selected photometric catalog, along with accurate photometric redshifts. The redshifts are computed with 37 (20) filters in the COSMOS (AEGIS) fields, combining the NIR medium-bandwidth data with existing UV (Galaxy Evolution Explorer), visible and NIR (Canada-France-Hawaii Telescope and Subaru Telescope), and mid-IR (Spitzer/IRAC) imaging. We find excellent agreement with publicly available spectroscopic redshifts, with {sigma}_z_/(1+z)~1%-2% for ~4000 galaxies at z=0-3. The NMBS catalogs contain ~13000 galaxies at z>1.5 with accurate photometric redshifts and rest-frame colors. Due to the increased spectral resolution obtained with the five NIR medium-band filters, the median 68% confidence intervals of the photometric redshifts of both quiescent and star-forming galaxies are a factor of about two times smaller when comparing catalogs with medium-band NIR photometry to NIR broadband photometry.
1205. 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.
1206. 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.
1207. 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%.
1208. 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.
1209. 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.
1210. 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.