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16051. Type 1 vs 2 X-ray-selected COSMOS AGNs & environment
ID:
ivo://CDS.VizieR/J/ApJ/878/11
Title:
Type 1 vs 2 X-ray-selected COSMOS AGNs & environment
Short Name:
J/ApJ/878/11
Date:
21 Oct 2021
Publisher:
CDS
Description:
The unified model of active galactic nuclei (AGNs) proposes that different AGN optical spectral types are caused by different viewing angles with respect to an obscuring "torus". Therefore, this model predicts that type 1 and type 2 AGNs should have similar host-galaxy properties. We investigate this prediction with 2463 X-ray-selected AGNs in the COSMOS field. We divide our sample into type 1 and type 2 AGNs based on their spectra, morphologies, and variability. We derive their host-galaxy stellar masses (M_*_) through spectral energy distribution (SED) fitting, and we find that the hosts M_*_ of type 1 AGNs tend to be slightly smaller than those of type 2 AGNs by {Delta}logM_*_~0.2dex (~4{sigma} significance). Besides deriving star formation rates (SFRs) from SED fitting, we also utilize far-infrared (FIR) photometry and a stacking method to obtain FIR-based SFRs. We find that the SFRs of type 1 and type 2 sources are similar once their redshifts and X-ray luminosities are controlled. We also investigate the cosmic environment, and we find that the surface number densities (sub-Mpc) and cosmic-web environments (~1-10Mpc) are similar for both populations. In summary, our analyses show that the host galaxies of type 1 and type 2 AGNs have similar SFRs and cosmic environments in general, but the former tend to have a lower M_*_ than the latter. The difference in M_*_ indicates that the AGN unification model is not strictly correct, and both host galaxy and torus may contribute to the optical obscuration of AGNs.
16052. TZ For OIFITS files
ID:
ivo://CDS.VizieR/J/A+A/586/A35
Title:
TZ For OIFITS files
Short Name:
J/A+A/586/A35
Date:
21 Oct 2021
Publisher:
CDS
Description:
Independent distance estimates are particularly useful to check the precision of other distance indicators, while accurate and precise masses are necessary to constrain evolution models. The goal is to measure the masses and distance of the detached eclipsing-binary TZ For with a precision level lower than 1% using a fully geometrical and empirical method. We obtained the first interferometric observations of TZ For with the VLTI/PIONIER combiner, which we combined with new and precise radial velocity measurements to derive its three-dimensional orbit, masses, and distance.
16053. U-band dropouts in Hubble Ultra Deep Field
ID:
ivo://CDS.VizieR/J/AJ/132/1023
Title:
U-band dropouts in Hubble Ultra Deep Field
Short Name:
J/AJ/132/1023
Date:
21 Oct 2021
Publisher:
CDS
Description:
We combine data from the extremely deep Hubble Space Telescope U (F300W) image, obtained using WFPC2 as part of the parallel observations of the Hubble Ultra Deep Field campaign, with BVi images from the Great Observatories Origins Deep Survey to identify a sample of Lyman break galaxies in the redshift range 2.0<=z<=3.5. We use recent stellar population synthesis models with a wide variety of ages, metallicities, redshifts, and dust content, and a detailed representation of the HI cosmic opacity as a function of redshift to model the colors of galaxies in our combination of WFPC2 and ACS filters. Using these models, we derive improved color selection criteria that provide a clean selection of relatively unobscured star-forming galaxies in this redshift range. Our WFPC2 F300W image is the deepest image ever obtained at that wavelength. The 10 limiting magnitude measured over 0.2arcsec^2^ is 27.5mag in the WFPC2 F300W image, about 0.5mag deeper than the F300W image in the Hubble Deep Field (HDF)-North.
16054. U-band photometry in sigma Orionis region
ID:
ivo://CDS.VizieR/J/A+A/525/A47
Title:
U-band photometry in sigma Orionis region
Short Name:
J/A+A/525/A47
Date:
21 Oct 2021
Publisher:
CDS
Description:
This paper presents the results of an U band survey with FORS1/VLT of a large area in the sigma Ori star-forming region. We combine the U-band photometry with literature data to compute accretion luminosity and mass accretion rates from the U-band excess emission for all objects (187) detected by Spitzer in the FORS1 field and classified by Hernandez et al. (2007, Cat. J/ApJ/662/1067) as likely members of the cluster.
16055. U-band photometry of 17 WINGS clusters
ID:
ivo://CDS.VizieR/J/A+A/561/A111
Title:
U-band photometry of 17 WINGS clusters
Short Name:
J/A+A/561/A111
Date:
21 Oct 2021
Publisher:
CDS
Description:
This paper belongs to a series presenting the WIde Field Nearby Galaxy-cluster Survey (WINGS). The WINGS project has collected wide-field, optical (B,V), and near-infrared (J,K) imaging as well as medium resolution spectroscopy of galaxies in a sample of 76 X-ray selected nearby clusters (0.04<z<0.07) with the aim of establishing a reference sample for evolutionary studies of galaxies and galaxy clusters. We present the U-band photometry of galaxies and stars in the fields of 17 clusters of the WINGS sample. We also extend the original B- and V-band photometry (WINGS-OPT) for 9 and 6 WINGS clusters to a larger field of view. We used both the new and already existing B-band photometry to obtain reliable (U-B) colors of galaxies within three fixed apertures in kpc. To this aim, we particular care the astrometric precision in the reduction procedure. Since not all the observations were taken in good transparency conditions, the photometric calibration was partly obtained by relying on the SDSS and WINGS-OPT photometry for the U- and optical bands, respectively. We provide U-band (also B- and V-band, where possible) total magnitudes of stars and galaxies in the fields of clusters. For galaxies only, the catalogs also provide geometrical parameters and carefully centered aperture magnitudes. The internal consistency of magnitudes was checked for clusters imaged with different cameras, while the external photometric consistency was obtained by comparison with the WINGS-OPT and SDSS surveys. The photometric catalogs presented here add the U-band information to the WINGS database for extending the spectral energy distribution (SED) of the galaxies, in particular in the ultraviolet (UV) wavelengths which are fundamental for deriving the star formation rate (SFR) properties.
16056. UBgRIJKs photometry in the FORS Deep Field
ID:
ivo://CDS.VizieR/J/A+A/398/49
Title:
UBgRIJKs photometry in the FORS Deep Field
Short Name:
J/A+A/398/49
Date:
21 Oct 2021
Publisher:
CDS
Description:
The FORS Deep Field project is a multi-colour, multi-object spectroscopic investigation of a 7' times 7' region near the south galactic pole based mostly on observations carried out with the FORS instruments attached to the VLT telescopes. It includes the QSO Q0103-260 (z=3.36). The goal of this study is to improve our understanding of the formation and evolution of galaxies in the young Universe. In this paper the field selection, the photometric observations, and the data reduction are described. The source detection and photometry of objects in the FORS Deep Field is discussed in detail. A combined B and I selected UBgRIJKs photometric catalog of 8753 objects in the FDF is presented and its properties are briefly discussed. The formal 50% completeness limits for point sources, derived from the coadded images, are 25.64, 27.69, 26.86, 26.68, 26.37, 23.60 and 21.57 in U, B, g, R, I, J and Ks (Vega-system), respectively. A comparison of the number counts in the FORS Deep Field to those derived in other deep field surveys shows very good agreement.
16057. UBIc photometry of ACO2390 early-type galaxies
ID:
ivo://CDS.VizieR/J/MNRAS/358/233
Title:
UBIc photometry of ACO2390 early-type galaxies
Short Name:
J/MNRAS/358/233
Date:
21 Oct 2021
Publisher:
CDS
Description:
We investigate a spectroscopic sample of 48 early-type galaxies in the rich cluster Abell 2390 at z=0.23 and 48 early-type galaxies from a previously published survey of Abell 2218 at z=0.18. The spectroscopic data of A2390 are based on multi-object spectroscopy using the multi-object spectrograph for Calar Alto at the 3.5-m telescope on Calar Alto Observatory and are complemented by ground-based imaging using the 5.1-m Hale telescope and Hubble Space Telescope (HST) observations in the F555W and F814W filters.
16058. u(bj)r & BV photometry of blue HB stars
ID:
ivo://CDS.VizieR/J/MNRAS/352/285
Title:
u(bj)r & BV photometry of blue HB stars
Short Name:
J/MNRAS/352/285
Date:
21 Oct 2021
Publisher:
CDS
Description:
This is the second in a series of papers presenting a new calculation of the mass of the Galaxy based on radial velocities and distances for a sample of faint 16<B<21.3 field blue horizontal-branch (BHB) stars. We present accurate BV CCD photometry and spectra for 142 candidate A-type stars selected from ubjr photometry of UK Schmidt telescope plates in six high-Galactic-latitude fields. Classification of these candidates produces a sample of 60 BHB stars at distances of 11-52kpc from the Sun (mean 28kpc), with heliocentric line-of-sight velocities accurate to 15km/s, and distance errors <10 per cent. We provide a summary table listing coordinates and velocities of these stars.
16059. UBRI photometry of NGC 3379 globular clusters
ID:
ivo://CDS.VizieR/J/MNRAS/345/949
Title:
UBRI photometry of NGC 3379 globular clusters
Short Name:
J/MNRAS/345/949
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present wide-area UBRI photometry for globular clusters around the Leo group galaxy NGC 3379. Globular cluster candidates are selected from their B-band magnitudes and their (U-B)_0_ versus (B-I)_0_ colours. A colour-colour selection region was defined from photometry of the Milky Way and M31 globular cluster systems. We detect 133 globular cluster candidates, which supports previous claims of a low specific frequency for NGC 3379.
16060. UBRI Photometry of Quasars
ID:
ivo://CDS.VizieR/J/AJ/128/544
Title:
UBRI Photometry of Quasars
Short Name:
J/AJ/128/544
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present UBRI photometry and spectra for 60 quasars found within 1{deg}^2^ centered on the J0053+1234 region, which has been the subject of the Caltech Faint Galaxy Redshift Survey. Candidate quasars were selected by their ultraviolet excess with respect to the stellar locus and confirmed spectroscopically. The quasars span a wide range in brightness (17.5<B<21.6) and redshift (0.43<z<2.38).

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