- ID:
- ivo://CDS.VizieR/J/AJ/158/16
- Title:
- Identification of RR Lyrae stars from the DES
- Short Name:
- J/AJ/158/16
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Many studies have shown that RR Lyrae variable stars (RRL) are powerful stellar tracers of Galactic halo structure and satellite galaxies. The Dark Energy Survey (DES), with its deep and wide coverage (g~23.5 mag in a single exposure; over 5000 deg^2^) provides a rich opportunity to search for substructures out to the edge of the Milky Way halo. However, the sparse and unevenly sampled multiband light curves from the DES wide-field survey (a median of four observations in each of grizY over the first three years) pose a challenge for traditional techniques used to detect RRL. We present an empirically motivated and computationally efficient template-fitting method to identify these variable stars using three years of DES data. When tested on DES light curves of previously classified objects in SDSS stripe 82, our algorithm recovers 89% of RRL periods to within 1% of their true value with 85% purity and 76% completeness. Using this method, we identify 5783 RRL candidates, ~28% of which are previously undiscovered. This method will be useful for identifying RRL in other sparse multiband data sets.
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Search Results
- ID:
- ivo://CDS.VizieR/J/AZh/73/835
- Title:
- Identifications of objects from RC Catalog
- Short Name:
- J/AZh/73/835
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Results from a continuing program for identification of sources from the RC catalog (from observations with the RATAN-600 radio telescope) with the APM (Automatic Plate Measuring) Northern Sky Catalogs available via the Internet are presented. The coordinate accuracy for the optical objects is better than 1".
- ID:
- ivo://CDS.VizieR/J/ApJS/254/26
- Title:
- Identifying 3FHL. V. CTIO-COSMOS spectra
- Short Name:
- J/ApJS/254/26
- Date:
- 19 Jan 2022 00:35:09
- Publisher:
- CDS
- Description:
- As a follow-up to the optical spectroscopic campaign aimed at achieving completeness in the Third Catalog of Hard Fermi-LAT Sources (3FHL), we present here the results of a sample of 28 blazars of an uncertain type observed using the 4m telescope at Cerro Tololo Inter-American Observatory in Chile. Out of these 28 sources, we find that 25 are BL Lacertae objects (BL Lacs) and 3 are flat-spectrum radio quasars (FSRQs). We measure redshifts or lower limits for 16 of these blazars, and it is observed that the 12 remaining blazars have featureless optical spectra. These results are part of a more extended optical spectroscopy follow-up campaign for 3FHL blazars, where, until now, 51 blazars of an uncertain type have been classified into BL Lac and FSRQ categories. Furthermore, this campaign has resulted in redshift measurements and lower limits for 15 of these sources. Our results contribute toward attaining a complete sample of blazars above 10 GeV, which then will be crucial in extending our knowledge on blazar emission mechanisms and the extragalactic background light.
- ID:
- ivo://CDS.VizieR/J/A+A/548/A16
- Title:
- Improved astrometry bor BE74 stars
- Short Name:
- J/A+A/548/A16
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Accurate astrometry is required to reliably cross-match 20th-century catalogues against 21st-century surveys. The present work aims to provide such astrometry for the 625 entries of the Bohannan & Epps (BE74; 1974A&AS...18...47B) catalogue of H{alpha} emission-line stars. BE74 targets have been individually identified in digital images and, in most cases, unambiguously matched to entries in the UCAC4 (I/322) astrometric catalogue.
- ID:
- ivo://CDS.VizieR/J/ApJS/224/15
- Title:
- Improved 2Ms and 250ks Chandra catalogs
- Short Name:
- J/ApJS/224/15
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present improved point-source catalogs for the 2Ms Chandra Deep Field-North (CDF-N) and the 250ks Extended Chandra Deep Field-South (E-CDF-S) Surveys, implementing a number of recent improvements in Chandra source-cataloging methodology. For CDF-N/E-CDF-S, we provide a main catalog that contains 683/1003 X-ray sources detected with wavdetect at a false-positive probability threshold of 10^-5^ that also satisfy a binomial-probability source-selection criterion of P<=0.004/P<0.002. Such an approach maximizes the number of reliable sources detected: a total of 196/275 main-catalog sources are new compared to the Alexander+ (2003, J/AJ/126/539) CDF-N/Lehmer+ (2005, J/ApJS/161/21) E-CDF-S main catalogs. We also provide CDF-N/E-CDF-S supplementary catalogs that consist of 72/56 sources detected at the same wavdetect threshold and having P of 0.004-0.1/0.002-0.1 and Ks<=22.9/Ks<=22.3mag counterparts. For all ~1800 CDF-N and E-CDF-S sources, including the ~500 newly detected ones (these being generally fainter and more obscured), we determine X-ray source positions utilizing centroid and matched-filter techniques; we also provide multiwavelength identifications, apparent magnitudes of counterparts, spectroscopic and/or photometric redshifts, basic source classifications, and estimates of observed active galactic nucleus and galaxy source densities around respective field centers. Simulations show that both the CDF-N and E-CDF-S main catalogs are highly reliable and reasonably complete. Background and sensitivity analyses indicate that the on-axis mean flux limits reached represent a factor of ~1.5-2.0 improvement over the previous CDF-N and E-CDF-S limits. We make our data products publicly available.
- ID:
- ivo://CDS.VizieR/J/A+A/463/175
- Title:
- Infrared study of IRAS 14416-5937 region
- Short Name:
- J/A+A/463/175
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have carried out an infrared study of the southern Galactic massive star-forming region associated with IRAS 14416-5937. This star-forming region has been mapped simultaneously in two far infrared bands at ~150 & 210 micron using the TIFR 1-m balloon borne telescope with ~1' angular resolution. We have used the 2MASS JHKs data as well as the GLIMPSE-Spitzer data of this region to study the stellar populations of the embedded young cluster. This region comprises of two sources designated as A and B, separated by ~2pc. The spectrum of a region located close to the source A obtained using the Long Wavelength Spectrometer (LWS) on-board the Infrared Space Observatory (ISO) is presented. Emission from warm dust and the unidentified infrared bands (UIBs) is estimated using the mid-infrared data from the MSX survey. The spatial distribution of the temperature of cool dust and optical depth at 200 micron have been obtained taking advantage of the similar beams in the two TIFR bands. A number of atomic fine structure lines have been detected in the ISO-LWS spectrum, which have been used to estimate the electron density and the effective temperature of the ionising radiation in this region. From the near and mid infrared images, we identify a dust lane due north-west direction of the source A. The dust lane is populated by Class I type sources. Class II type sources are found further along the dust lane as well as below it. Self consistent radiative transfer models of the two sources (A and B) are in good agreement with the observed spectral energy distributions. The spatial distribution of young stellar objects in and around the dust lane suggests that active star formation is taking place along the dust lane and is possibly triggered by the expanding HII regions of A and B.
- ID:
- ivo://CDS.VizieR/VII/236
- Title:
- Interacting galaxies catalogue
- Short Name:
- VII/236
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The present edition unifies two parts of Catalogue of interacting galaxies by B.A. Vorontsov-Velyaminov (1959VV....C......0V, 1970, 1977A&AS...28....1V). It contains 852 known interacting VV-systems and 1162 new objects taken from the comments on the galaxies in Morphological catalogues of galaxies by Vorotsov-Velyaminov et al. (1962, 1963, 1964, 1968, 1974, Cats. <VII/62>, <VII/100>) with numbers from VV853 to VV2014. The classification of interacting galaxies is given in accord with the suggestion s of Vorotsov-Velyaminov. The catalogue contains new information for the galaxies included taken from the NEDA-NASA/IPAC extragalactic data base.
- ID:
- ivo://CDS.VizieR/J/A+A/403/555
- Title:
- Interplanetary Scintillation Pushchino Survey
- Short Name:
- J/A+A/403/555
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Interplanetary scintillating (IPS) radio sources from the Pushchino Survey (PS) in the area of 0.11sr have been cross-identified with objects from the 7C and FIRST catalogues. We have obtained improved positions of IPS radio sources, which are necessary for their optical identification. The data on sizes and morphology provided by the FIRST catalogue have shown that more than 50% of IPS radio sources are single and compact (<3") at {nu}=1400MHz. Most of them belong to the class of compact steep spectrum radio sources. About 15% of IPS radio sources are single partially resolved FIRST objects (sizes of 3"-9") and another 11% are double radio sources with compact components. The remaining 22% have larger sizes and, as a rule, a more complex structure too. Because IPS sources certainly contain an appreciable part of their radiation at low frequencies (100MHz) in very compact (~0.1") components and have steep spectra, we hope that a significant part of the Pushchino Survey objects are very probable candidates for steep spectrum quasars.
- ID:
- ivo://CDS.VizieR/J/A+A/421/455
- Title:
- Interplanetary Scintillation Pushchino Survey II
- Short Name:
- J/A+A/421/455
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of optical identification of 248 interplanetary scintillating (IPS) radio sources from the Pushchino Survey (PS) in the area of 0.11sr with the center at RA=10h28m, DE=+41{deg}. All 260 counterparts of IPS radio sources from the 7C and FIRST catalogues, which had been found in Paper I (Cat. <J/A+A/403/555>), were considered. We used USNO-B1.0 catalogue (limiting magnitude m_R_~21) for the optical identification and searched the literature to find optical data for fainter objects. Photometric and spectroscopic observations were conducted on the 1m and 6m telescopes of SAO RAS. Optical magnitudes or deep limits for 22 objects and redshifts for 26 ones have been obtained. In total, we collected optical data for 116 (68 with redshift) counterparts of the PS radio sources. For the subsample of the PS quasars (41 objects) the redshift distribution was compared to those of several other samples of quasars (BRL, 3CRR, MQS, B3-VLA, 7CRS I-III and PKS 0.25Jy) which have complete or nearly complete redshift information.
- ID:
- ivo://CDS.VizieR/J/ApJ/756/72
- Title:
- IRAC identifications for 510 AEGIS20 radio sources
- Short Name:
- J/ApJ/756/72
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Infrared 3.6-8{mu}m images of the Extended Groth Strip yield plausible counterpart identifications for all but one of 510 radio sources in the AEGIS20 S(1.4GHz)>50{mu}Jy sample. This is the first such deep sample that has been effectively 100% identified. Achieving the same identification rate at R band would require observations reaching R_AB_>27. Spectroscopic redshifts are available for 46% of the sample and photometric redshifts for an additional 47%. Almost all of the sources with 3.6{mu}m AB magnitudes brighter than 19 have spectroscopic redshifts z<1.1, while fainter objects predominantly have photometric redshifts with 1<~z<~3. Unlike more powerful radio sources that are hosted by galaxies having large stellar masses within a relatively narrow range, the AEGIS20 counterparts have stellar masses spanning more than a factor of 10 at z~1. The sources are roughly 10%-15% starbursts at z<~0.5 and 20%-25% active galactic nuclei mostly at z>1 with the remainder of uncertain nature.
