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2331. Catalogue of X-Ray Binaries
ID:
ivo://CDS.VizieR/V/90
Title:
Catalogue of X-Ray Binaries
Short Name:
V/90
Date:
21 Oct 2021
Publisher:
CDS
Description:
The objects described in this catalog are X-Ray binaries, i.e., semi-detached binary stars in which matter is transferred from a usually more or less normal star to a neutron star or black hole. Thus, cataclysmic variables are not included. The tables provide basic information of the systems as well as selected references. The tables contain 124 low-mass and 69 high mass X-ray binaries.
2332. Catalogue of X-ray luminous clusters members
ID:
ivo://CDS.VizieR/J/A+A/606/A122
Title:
Catalogue of X-ray luminous clusters members
Short Name:
J/A+A/606/A122
Date:
21 Oct 2021
Publisher:
CDS
Description:
A robust determination of galaxy cluster mass is crucial to use them as cosmological probes, or to study the physics governing their formation and evolution. Applying various estimators on well-defined cluster samples is a mandatory step in characterising their respective systematics. Our main goal is to compare the results of three dynamical mass estimators to the X-ray hydrostatic values. Here we focus on massive galaxy clusters at intermediate redshifts z~0.3. We estimated dynamical masses with the virial theorem, the Jeans equation, and the caustic method using wide-field VIMOS spectroscopy; the hydrostatic masses were obtained previously from XMM-Newton observations.We investigated the role of colour selection and the impact of substructures on the dynamical estimators.
2333. Catalogues from a deep 327 MHz Westerbork Survey
ID:
ivo://CDS.VizieR/VIII/19
Title:
Catalogues from a deep 327 MHz Westerbork Survey
Short Name:
VIII/19
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of a deep survey of six fields with the Westerbork Synthesis Radio Telescope at 327 MHz. In total we have detected ~4500 sources brighter than our 5-sigma noise level, which ranges from 2.4-3.5 mJy/beam, over an area of ~95 square degrees. For four fields we also obtained 608 MHz observations, for the remaining two fields 608 MHz observations were already available. We present the source catalogues at both frequencies and derive source counts and spectral indices. The data were calibrated using the DWARF redundancy package and absolute calibration is based on 3C286, using a flux of 26.93 Jy at 327 Mhz and 21.47 Jy at 608 MHz. The source parameters were determined using a gaussian fitting procedure for all but the most complex sources and statistical corrections for noise bias were applied. As part of my PhD-thesis at Leiden Observatory I made the following surveys at 327 and 608 MHz using the Westerbork Synthesis Radio Telescope: -------------------------------------------------------------------------- 64W2: Lynx, 327 MHz only (this field has been mapped at this frequency before by M.J.A. Oort (thesis), I've added a 2 after the W to indicate the revised list), numbers do not correspond because the present survey is more sensitive. 69W : Draco, a survey of 2 overlapping fields at 327 MHz and 6 fields at 608 MHz. 70W : Umi, 327 MHz only, one field. 75W : OH471, one 327 MHz field and three 608 MHz fields 76W : Cam, one 327 MHz field and three 608 MHz fields -------------------------------------------------------------------------- Sources detected at both frequencies have corresponding numbers in the 327 MHz (92cm) and 608 MHz (50cm) lists. Multiple sources are indicated by a '*' after the name, their components by 'A','B', etc. Components of multiple sources do not necessarily correspond between the two frequencies, also in some cases one or more components may not be detected at the other frequency. The .tex files are in plain TeX format The .dat files were written with the following format (fortran): FORMAT(A8,1X,F9.2,1X,F4.2,1X,F9.1,1X,F4.1,1X,F8.2,1X,F7.2,1X,A2, 1 1X,F5.1,1X,F4.1,1X,F4.0,1X,F3.0,1X,F5.1,1X,F5.2,1X,F7.2, 1 1X,F5.2,1X,F5.2)
2334. Catalogues of Blue Horizontal Branch Stars
ID:
ivo://CDS.VizieR/J/A+A/654/A107
Title:
Catalogues of Blue Horizontal Branch Stars
Short Name:
J/A+A/654/A107
Date:
22 Feb 2022
Publisher:
CDS
Description:
Blue horizontal-branch stars evolve from low-mass stars that have completed their main-sequence lifetimes and undergone a helium flash at the end of their red-giant phase. As such, blue horizontal-branch stars are very old objects that can be used as markers in studies of the Galactic structure and formation history. To create a clean sky catalogue of blue horizontal-branch stars, we cross-matched the Gaia data release 2 (DR2) dataset with existing reference catalogues to define selection criteria based on Gaia DR2parameters. Following the publication of Gaia early data release 3 (EDR3), these methods were verified and subsequently applied to this latest release. Previous catalogues of blue horizontal-branch stars were developed using spectral analyses or were restricted to individual globular clusters. The purpose of this catalogue is to identify a set of blue horizontal-branch star candidates that have been selected using photometric and astrometric observations and exhibits a low contamination rate. This has been deemed important as the success of the Gaia mission has changed the way that targets are selected for large-scale spectroscopic surveys, meaning that far fewer spectra will be acquired for blue horizontal-branch stars in the future unless they are specifically targeted. We cross-matched reference blue horizontal-branch datasets with the Gaia DR2 database and defined two sets of selection criteria. Firstly, in Gaia DR2 - colour and absolute G magnitude space, and secondly, in Gaia DR2 - colour and reduced proper motion space. The main-sequence contamination in both subsets of the catalogue was reduced, at the expense of completeness, by concentrating on the Milky Way's Galactic halo, where relatively young main-sequence stars were not expected. The entire catalogue is limited to those stars with no apparent neighbours within 5 arcsec. These methods were verified and subsequently applied to theGaia Early Data Release 3 (EDR3). We present a catalogue, based on Gaia EDR3, of 57377 blue horizontal-branch stars. The Gaia EDR3 parallax was used in selecting 16794 candidates and the proper motions were used to identify a further 40583 candidates.
2335. Catalogues of variable AGNs
ID:
ivo://CDS.VizieR/J/A+A/584/A106
Title:
Catalogues of variable AGNs
Short Name:
J/A+A/584/A106
Date:
21 Oct 2021
Publisher:
CDS
Description:
Upcoming large area sky surveys like Euclid and eROSITA, which are dedicated to studying the role of dark energy in the expansion history of the Universe and the three-dimensional mass distribution of matter, crucially depend on accurate photometric redshifts. The identification of variable sources, such as active galactic nuclei (AGNs), and the achievable redshift accuracy for varying objects are important in view of the science goals of the Euclid and eROSITA missions. We probe AGN optical variability for a large sample of X-ray-selected AGNs in the XMM-COSMOS field, using the multi-epoch light curves provided by the Pan-STARRS1 (PS1) 3n and Medium Deep Field surveys. To quantify variability we employed a simple statistic to estimate the probability of variability and the normalized excess variance to measure the variability amplitude. Utilizing these two variability parameters, we defined a sample of varying AGNs for every PS1 band. We investigated the influence of variability on the calculation of photometric redshifts by applying three different input photometry sets for our fitting procedure. For each of the five PS1 bands g_P1_, r_P1_, i_P1_, z_P1_, and y_P1_, we chose either the epochs minimizing the interval in observing time, the median magnitude values, or randomly drawn light curve points to compute the redshift. In addition, we derived photometric redshifts using PS1 photometry extended by GALEX/IRAC bands.
2336. Catching the radio flare in CTA 102
ID:
ivo://CDS.VizieR/J/A+A/551/A32
Title:
Catching the radio flare in CTA 102
Short Name:
J/A+A/551/A32
Date:
21 Oct 2021
Publisher:
CDS
Description:
Very Long Baseline Interferometry (VLBI) observations can resolve the radio structure of active galactic nuclei (AGN) and provide estimates of the structural and kinematic characteristics on parsec-scales in their jets. The changes in the kinematics of the observed jet features can be used to study the physical conditions in the innermost regions of these sources. We performed multifrequency multiepoch Very Long Baseline Array (VLBA) observations of the blazar CTA102 during its 2006 radio flare, the strongest ever reported for this source. These observations provide an excellent opportunity to investigate the evolution of the physical properties of blazars, especially during these flaring events. We want to study the kinematic changes in the source during the strong radio outburst in April 2006 and test the assumption of a shock-shock interaction. This assumption is based on the analysis and modeling of the single-dish observations of CTA 102 (Paper I, 2011A&A...531A..95F). In this paper we study the kinematics of CTA 102 at several frequencies using VLBI observations. From the modeled jet features we derived estimates for the evolution of the physical parameters, such as the particle density and the magnetic field. Furthermore ,we combined our observations during the 2006 flare with long-term VLBA monitoring of the source at 15 GHz and 43 GHz We cross-identified seven features throughout our entire multifrequency observations and find evidence of two possible recollimation shocks around 0.1mas (deprojected 18pc at a viewing angle of 2.6{deg} and 6.0mas (deprojected 1kpc) from the core. The 43GHz observations reveal a feature ejected at epoch t_ej_=2005.9+/-0.2, which could be connected to the 2006 April radio flare. Furthermore, this feature might be associated with the traveling component involved in the possible shock-shock interaction, which gives rise to the observed double peak structure in the single-dish light curves reported in Paper I, 2011A&A...531A..95F.
2337. CaT/[Fe/H] calibration for Galactic bulge stars
ID:
ivo://CDS.VizieR/J/A+A/580/A121
Title:
CaT/[Fe/H] calibration for Galactic bulge stars
Short Name:
J/A+A/580/A121
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a new calibration of the calcium II triplet equivalent widths versus [Fe/H], constructed upon K giant stars in the Galactic bulge. This calibration will be used to derive iron abundances for the targets of the GIBS survey, and is in general especially well suited for solar and supersolar metallicity giants, which are typical of external massive galaxies. To obtain the calibration, about 150 bulge K giants were observed with the GIRAFFE spectrograph at the VLT with a resolution of R~20000 and at R~6000. In the first case, the spectra allowed us to directly determine the Fe abundances from several unblended Fe lines, deriving what we call here high-resolution [Fe/H] measurements. The low-resolution spectra allowed us to measure equivalent widths of the two strongest lines of the near-infrared calcium II triplet at 8542 and 8662{AA}. By comparing the two measurements, we derived a relation between calcium equivalent widths and [Fe/H] that is linear over the metallicity range probed here, -1<[Fe/H]<+0.7. By adding a small second-order correction based on literature globular cluster data, we derived the unique calibration equation [Fe/H]_CaT_=-3.150+0.432W'+0.006W'^2^, with an rms dispersion of 0.197dex, valid across the whole metallicity range -2.3<[Fe/H]<+0.7.
2338. CaT in 903 globular clusters
ID:
ivo://CDS.VizieR/J/MNRAS/426/1475
Title:
CaT in 903 globular clusters
Short Name:
J/MNRAS/426/1475
Date:
21 Oct 2021
Publisher:
CDS
Description:
Although the colour distribution of globular clusters in massive galaxies is well known to be bimodal, the spectroscopic metallicity distribution has been measured in only a few galaxies. After redefining the calcium triplet index-metallicity relation, we use our relation to derive the metallicity of 903 globular clusters in 11 early-type galaxies. This is the largest sample of spectroscopic globular cluster metallicities yet assembled. We compare these metallicities with those derived from Lick indices finding good agreement. In six of the eight galaxies with sufficient numbers of high-quality spectra we find bimodality in the spectroscopic metallicity distribution. Our results imply that most massive early-type galaxies have bimodal metallicity as well as colour distributions. This bimodality suggests that most massive early-type galaxies experienced two periods of star formation.
2340. CatWISE2020 Catalog
ID:
ivo://irsa.ipac/WISE/Catalog/CatWISE2
Title:
CatWISE2020 Catalog
Short Name:
CatWISE2
Date:
02 Dec 2020 19:45:36
Publisher:
NASA/IPAC Infrared Science Archive
Description:
The CatWISE2020 catalog contains positions and brightnesses for 1,890,715,640 sources selected from combined WISE and NEOWISE all-sky survey data collected from 2010 to 2018 at 3.4 and 4.6 microns (W1 and W2). CatWISE adapts AllWISE software to measure the sources in co-added images created from six month subsets of these data, each representing one coverage of the inertial sky, or epoch. The catalog includes the measured motion of sources in 12 epochs over the 8 year span of the data.

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