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5231. Turin-SyCAT, Seyferts multifrequency catalog
ID:
ivo://CDS.VizieR/J/A+A/659/A32
Title:
Turin-SyCAT, Seyferts multifrequency catalog
Short Name:
J/A+A/659/A32
Date:
02 Mar 2022 06:48:51
Publisher:
CDS
Description:
We present the first release of Turin-SyCAT, a multifrequency catalog of Seyfert galaxies. We selected Seyfert galaxies considering criteria based on radio, infrared, and optical properties and starting from sources belonging to hard X-ray catalogs and surveys. We visually inspected optical spectra available for all selected sources. We adopted homogeneous and stringent criteria in the source selection aiming at reducing the possible contamination from other source classes. Our final catalog includes 351 Seyfert galaxies distinguished in 233 type 1 and 118 type 2. Type 1 Seyfert galaxies appear to have mid-IR colors similar to blazars, but are distinguished from them by their radio-loudness. Additionally, Seyfert 2 galaxies have mid-IR colors more similar to quasars than BL Lac objects. As expected from their spectral properties, type 1 and 2 Seyfert galaxies show a clear distinction when using the u-r color. Finally, we found a tight correlation between the mid-IR fluxes at both 12 and 22 um (i.e., F12 and F22, respectively) and hard X-ray fluxes between 15 and 150 keV. Both Seyfert types appear to follow the same trend and share similar values of the ratios of F12 and F22 to FHX in agreement with expectations of the AGN unification scenario. As future perspectives, the Turin-SyCAT will then be used to search for heavily obscured Seyfert galaxies among unidentified hard X-ray sources, given the correlation between mid-IR and hard X-rays, and to investigate their large-scale environments.
5232. Two-Micron Sky Survey (TMSS)
ID:
ivo://CDS.VizieR/II/2B
Title:
Two-Micron Sky Survey (TMSS)
Short Name:
II/2B
Date:
21 Oct 2021
Publisher:
CDS
Description:
The catalog, giving sources of emission in the 2.2-micrometer region for more than 5000 stars, represents a systematic survey of the Northern Hemisphere for stars brighter than third magnitude. The survey was carried out with a telescope at Mount Wilson, California, having a 62-inch diameter and an f/l aluminized epoxy mirror mounted equatorially. Radiation at an effective wavelength of 2.2 micrometers was detected by a lead sulfide photoconductive cell cooled by liquid nitrogen. In addition to the 2.2-micrometer detector array, radiation at an effective wavelength of 0.84 micrometers was detected by a simple silicon photovoltaic cell. The catalog includes right ascension and declination (B1950.0), K and I magnitudes, number of measurements, V magnitude, spectral types, cross identifications to the numbering systems of the General Catalogue, the Durchmusterung catalogs, the Bright Star Catalogue, and star names.
5233. Two new cataclysmic variables in Lyra
ID:
ivo://CDS.VizieR/J/other/PZ/31.3
Title:
Two new cataclysmic variables in Lyra
Short Name:
J/other/PZ/31.3
Date:
21 Oct 2021
Publisher:
CDS
Description:
I report on the discovery of two cataclysmic variables in the same field in Lyra, originally identified on the base of their magnitudes in the USNO-B1.0 catalog and on Palomar images. The historical light curves were analyzed from 300+ photographic plates of the Moscow collection, covering 35 years of observations. One of the two stars, USNO-B1.0 1320-0390658, is showing rather frequent outbursts from B~20 to B=15.2 and is likely a dwarf nova of the UGSS subtype. The other variable, USNO-B1.0 1321-0397655, with only one observed outburst in 1993, from B~19 to I=11.8, is either an UGWZ dwarf nova or a recurrent nova. In both cases, its next outburst can occur in the nearest future.
5234. Two new catalogs of blazar candidates
ID:
ivo://CDS.VizieR/J/ApJS/242/4
Title:
Two new catalogs of blazar candidates
Short Name:
J/ApJS/242/4
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present two catalogs of radio-loud candidate blazars whose Wide-Field Infrared Survey Explorer (WISE) mid-infrared colors are selected to be consistent with the colors of confirmed {gamma}-ray-emitting blazars. The first catalog is the improved and expanded release of the WISE Blazar-like Radio-Loud Sources (WIBRaLS) catalog presented by D'Abrusco et al. It includes sources detected in all four WISE filters, spatially cross-matched with radio sources in one of three radio surveys and radio-loud based on their q_22_ spectral parameter. WIBRaLS2 includes 9541 sources classified as BL Lacs, flat-spectrum radio quasars, or mixed candidates based on their WISE colors. The second catalog, called KDEBLLACS, based on a new selection technique, contains 5579 candidate BL Lacs extracted from the population of WISE sources detected in the first three WISE passbands ([3.4], [4.6], and [12]) only, whose mid-infrared colors are similar to those of confirmed, {gamma}-ray BL Lacs. Members of KDBLLACS are also required to have a radio counterpart and be radio-loud based on the parameter q_12_, defined similarly to the q_22_ used for the WIBRaLS2. We describe the properties of these catalogs and compare them with the largest samples of confirmed and candidate blazars in the literature. We cross-match the two new catalogs with the most recent catalogs of {gamma}-ray sources detected by the Fermi Large Area Telescope. Since spectroscopic observations of candidate blazars from the first WIBRaLS catalog within the uncertainty regions of {gamma}-ray unassociated sources confirmed that ~90% of these candidates are blazars, we anticipate that these new catalogs will again play an important role in the identification of the {gamma}-ray sky.
5235. Two secondary eclipses of WASP-12b with Spitzer
ID:
ivo://CDS.VizieR/J/ApJ/727/125
Title:
Two secondary eclipses of WASP-12b with Spitzer
Short Name:
J/ApJ/727/125
Date:
21 Oct 2021
Publisher:
CDS
Description:
We observed two secondary eclipses of the exoplanet WASP-12b using the Infrared Array Camera on the Spitzer Space Telescope. The close proximity of WASP-12b to its G-type star results in extreme tidal forces capable of inducing apsidal precession with a period as short as a few decades. This precession would be measurable if the orbit had a significant eccentricity, leading to an estimate of the tidal Love number and an assessment of the degree of central concentration in the planetary interior. An initial ground-based secondary-eclipse phase reported by Lopez-Morales et al. (0.510+/-0.002; 2010ApJ...716L..36L) implied eccentricity at the 4.5{sigma} level. The spectroscopic orbit of Hebb et al. (2009ApJ...693.1920H) has eccentricity 0.049+/-0.015, a 3{sigma} result, implying an eclipse phase of 0.509+/-0.007. However, there is a well-documented tendency of spectroscopic data to overestimate small eccentricities. Our eclipse phases are 0.5010+/-0.0006 (3.6 and 5.8um) and 0.5006+/-0.0007 (4.5 and 8.0um). An unlikely orbital precession scenario invoking an alignment of the orbit during the Spitzer observations could have explained this apparent discrepancy, but the final eclipse phase of Lopez-Morales et al. (0.510^+0.007^_-0.006_) is consistent with a circular orbit at better than 2{sigma}. An orbit fit to all the available transit, eclipse, and radial-velocity data indicates precession at <1{sigma}; a non-precessing solution fits better. We also comment on analysis and reporting for Spitzer exoplanet data in light of recent re-analyses.
5236. T/Y brown dwarfs with WISE photometry
ID:
ivo://CDS.VizieR/J/ApJ/753/156
Title:
T/Y brown dwarfs with WISE photometry
Short Name:
J/ApJ/753/156
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the discovery of another seven Y dwarfs from the Wide-field Infrared Survey Explorer (WISE). Using these objects, as well as the first six WISE Y dwarf discoveries from Cushing et al. (2011ApJ...743...50C), we further explore the transition between spectral types T and Y. We find that the T/Y boundary roughly coincides with the spot where the J-H colors of brown dwarfs, as predicted by models, turn back to the red. Moreover, we use preliminary trigonometric parallax measurements to show that the T/Y boundary may also correspond to the point at which the absolute H (1.6{mu}m) and W2 (4.6{mu}m) magnitudes plummet. We use these discoveries and their preliminary distances to place them in the larger context of the solar neighborhood. We present a table that updates the entire stellar and substellar constituency within 8pc of the Sun, and we show that the current census has hydrogen-burning stars outnumbering brown dwarfs by roughly a factor of six. This factor will decrease with time as more brown dwarfs are identified within this volume, but unless there is a vast reservoir of cold brown dwarfs invisible to WISE, the final space density of brown dwarfs is still expected to fall well below that of stars. We also use these new Y dwarf discoveries, along with newly discovered T dwarfs from WISE, to investigate the field substellar mass function. We find that the overall space density of late-T and early-Y dwarfs matches that from simulations describing the mass function as a power law with slope -0.5<{alpha}<0.0; however, a power law may provide a poor fit to the observed object counts as a function of spectral type because there are tantalizing hints that the number of brown dwarfs continues to rise from late-T to early-Y. More detailed monitoring and characterization of these Y dwarfs, along with dedicated searches aimed at identifying more examples, are certainly required.
5237. Tycho Input Catalogue, Revised version
ID:
ivo://CDS.VizieR/I/197A
Title:
Tycho Input Catalogue, Revised version
Short Name:
I/197A
Date:
21 Oct 2021
Publisher:
CDS
Description:
A Tycho Input Catalogue of three million stars brighter than V=12.1 has been prepared, for the needs of the Tycho mission (Hipparcos satellite). This catalogue results from the cross-matching of a subset of the Hubble Space Telescope Guide Star Catalog with the Hipparcos INCA database. References to these major catalogues, and details about the cross-matching procedures are to be found in the paper published in Astron. Astrophys. 258, 217-222 (May 1992). Among the 3,154,204 stars of the Tycho Input Catalogue, only a bit more than 1 million will appear in the final Tycho catalogue. A preliminary selection was done in the Recognition process, that was based on the first year of the satellite scientific mission (Halbwachs et al., =1994A&A...281L..25H). 1,049,971 stars were thus selected, and are flagged in this version of the Tycho Input Catalogue. The main file contains 3 154 204 records of 80 characters (total size: 256 Mbytes). It is split into four files tic1 to tic4 for easier manipulations. An annex file contains the following additional data for a subset of the stars: (a) the cross-identification with the Hipparcos Input Catalogue (117 778 records, flag 26) (b) the cross-matching with the INCA database (217 625 records, flag 20). The annex file contains 217 625 records (64 char., 14 Mbytes).
5238. Tycho-2 stars with IR excess
ID:
ivo://CDS.VizieR/J/MNRAS/363/1111
Title:
Tycho-2 stars with IR excess
Short Name:
J/MNRAS/363/1111
Date:
21 Oct 2021
Publisher:
CDS
Description:
Stars of all evolutionary phases have been found to have excess infrared emission due to the presence of circumstellar material. To identify such stars, we have positionally correlated the infrared Mid-Course Space Experiment (MSX) Point Source Catalogue (<V/114>) and the Tycho-2 optical catalogue (<I/259>). Near-mid-infrared colour criteria have been developed to select infrared excess stars. The search yielded 1938 excess stars; over half (979) have never previously been detected by IRAS. The excess stars were found to be young objects such as Herbig Ae/Be and Be stars, and evolved objects such as OH/IR (infrared) and carbon stars. A number of B-type excess stars were also discovered whose infrared colours could not be readily explained by known catalogued objects.
5239. Type-2 AGN from XMM-COSMOS bolometric output
ID:
ivo://CDS.VizieR/J/A+A/534/A110
Title:
Type-2 AGN from XMM-COSMOS bolometric output
Short Name:
J/A+A/534/A110
Date:
21 Oct 2021
Publisher:
CDS
Description:
Study of the multi-wavelength properties of a sample of 255 spectroscopically identified X-ray selected Type-2 AGN from the XMM-COSMOS survey. For each source, X-ray ID, spectroscopic redshift, logarithm of the 2-10keV luminosity, logarithm of the bolometric luminosity, bolometric correction, logarithm of the stellar mass, star formation rate, absolute magnitude M_U_, absolute magnitude M_V_, absolute magnitude M_J_ (Johnson-Kron-Cousin system), morphological class.
5240. Type 2 AGN host galaxies in Chandra-COSMOS
ID:
ivo://CDS.VizieR/J/ApJ/841/102
Title:
Type 2 AGN host galaxies in Chandra-COSMOS
Short Name:
J/ApJ/841/102
Date:
21 Oct 2021
Publisher:
CDS
Description:
We investigate the star formation properties of a large sample of ~2300 X-ray-selected Type 2 Active Galactic Nuclei (AGNs) host galaxies out to z~3 in the Chandra COSMOS Legacy Survey in order to understand the connection between the star formation and nuclear activity. Making use of the existing multi-wavelength photometric data available in the COSMOS field, we perform a multi-component modeling from far-infrared to near-ultraviolet using a nuclear dust torus model, a stellar population model and a starburst model of the spectral energy distributions (SEDs). Through detailed analyses of SEDs, we derive the stellar masses and the star formation rates (SFRs) of Type 2 AGN host galaxies. The stellar mass of our sample is in the range of 9<logM_stellar_/M_{sun}_<12 with uncertainties of ~0.19dex. We find that Type 2 AGN host galaxies have, on average, similar SFRs compared to the normal star-forming galaxies with similar M_stellar_ and redshift ranges, suggesting no significant evidence for enhancement or quenching of star formation. This could be interpreted in a scenario, where the relative massive galaxies have already experienced substantial growth at higher redshift (z>3), and grow slowly through secular fueling processes hosting moderate-luminosity AGNs.