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3871. Type 1 AGN at low z. III.
ID:
ivo://CDS.VizieR/J/MNRAS/431/836
Title:
Type 1 AGN at low z. III.
Short Name:
J/MNRAS/431/836
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the optical narrow-line ratios in a Sloan Digital Sky Survey (SDSS) based sample of 3175 broad H{alpha} selected type 1 active galactic nuclei (AGN), and explore their positions in the BPT diagrams as a function of the AGN and the host properties. We find the following: (1) the luminosities of all measured narrow lines (H{alpha}, H{beta}, [OIII], [NII], [SII], [OI]) show a Baldwin relation relative to the broad H{alpha} luminosity LbH{alpha}, with slopes in the range of 0.53-0.72. (2) About 20 percent of the type 1 AGN reside within the "Composite" and "star-forming" (SF) regions of the Baldwin, Phillips & Terlevich (BPT) diagrams. These objects also show excess narrow H{alpha} and ultraviolet (UV) luminosities, for their LbH{alpha}, consistent with contribution from star formation which dominates the narrow-lines emission, as expected from their positions in the BPT diagrams. (3) The type 1 which reside within the AGN region in the BPT diagrams, are offset to lower [SII]/H{alpha} and [NII]/H{alpha} luminosity ratios, compared to type 2 AGN. This offset is a selection effect, related to the lower AGN/host luminosity selection of the type 2 AGN selected from the SDSS galaxy sample. (4) The [NII]/H{alpha} and [NII]/[SII] ratios in type 1 AGN increase with the host mass, as expected if the mass-metallicity relation of quiescent galaxies holds for the AGN narrow-line region (NLR). (5) The broad lines optical Fe ii is higher for a higher [NII]/H{alpha}, at a fixed Lbol and Eddington ratio L/LEdd. This suggests that the broad line region metallicity is also related to the host mass. (6) The fraction of AGN which are low-ionization nuclear emission-line regions (LINERs) increases sharply with decreasing L/LEdd. This fraction is the same for type 1 and type 2 AGN. (7) The BPT position is unaffected by the amount of dust extinction of the optical-UV continuum, which suggests that the extincting dust resides on scales larger than the narrow-line region (NLR).
3872. Type 2 AGNs with double-peaked [OIII] lines
ID:
ivo://CDS.VizieR/J/ApJ/708/427
Title:
Type 2 AGNs with double-peaked [OIII] lines
Short Name:
J/ApJ/708/427
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a sample of 167 type 2 active galactic nuclei (AGNs) with double-peaked [OIII]4959,5007 narrow emission lines, selected from the Seventh Data Release of the Sloan Digital Sky Survey. The double-peaked profiles can be well modeled by two velocity components, blueshifted and redshifted from the systemic velocity. Half of these objects have a more prominent redshifted component. In cases where the H{beta} emission line is strong, it also shows two velocity components whose line-of-sight (LOS) velocity offsets are consistent with those of [OIII]. The relative LOS velocity offset between the two components is typically a few hundred km/s, larger by a factor of ~1.5 than the line full width at half maximum of each component. The offset correlates with the host stellar velocity dispersion {sigma}_*_. The host galaxies of this sample show systematically larger {sigma}_*_, stellar masses, and concentrations, and older luminosity-weighted mean stellar ages than a regular type 2 AGN sample matched in redshift, [OIII]5007 equivalent width, and luminosity; they show no significant difference in radio properties. These double-peaked features could be due to narrow-line region kinematics, or binary black holes.
3873. Type Ia supernova luminosities
ID:
ivo://CDS.VizieR/J/A+A/615/A68
Title:
Type Ia supernova luminosities
Short Name:
J/A+A/615/A68
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a fully consistent catalog of local and global properties of host galaxies of 882 Type Ia supernovae (SNIa) that were selected based on their light-curve properties, spanning the redshift range 0.01<z<1. This catalog corresponds to a preliminary version of the compilation sample and includes Supernova Legacy Survey (SNLS) 5-year data, Sloan Digital Sky Survey (SDSS), and low-redshift surveys. We measured low- and moderate-redshift host galaxy photometry in SDSS stacked and single-epoch images and used spectral energy distribution (SED) fitting techniques to derive host properties such as stellar mass and U-V rest-frame colors; the latter are an indicator of the luminosity-weighted age of the stellar population in a galaxy. We combined these results with high-redshift host photometry from the SNLS survey and thus obtained a consistent catalog of host stellar masses and colors across a wide redshift range. We also estimated the local observed fluxes at the supernova location within a proper distance radius of 3kpc, corresponding to the SNLS imaging resolution, and transposed them into local U-V rest-frame colors. This is the first time that local environments surrounding SNIa have been measured at redshifts spanning the entire Hubble diagram. Selecting SNIa based on host photometry quality, we then performed cosmological fits using local color as a third standardization variable, for which we split the sample at the median value. We find a local color step significance of -0.091+/-0.013mag (7{sigma}), which effect is as significant as the maximum mass step effect. This indicates that the remaining luminosity variations in SNIa samples can be reduced with a third standardization variable that takes the environment into account. Correcting for the maximum mass step correction of -0.094+/-0.013mag, we find a local color effect of -0.057+/-0.012mag (5{sigma}), which shows that additional information is provided by the close environment of SNIa. Departures from the initial choices were investigated and showed that the local color effect is still present, although less pronounced. We discuss the possible implications for cosmology and find that using the local color in place of the stellar mass results in a change in the measured value of the dark energy equation-of-state parameter of 0.6%. Standardization using local U-V color in addition to stretch and color reduces the total dispersion in the Hubble diagram from 0.15 to 0.14mag. This will be of tremendous importance for the forthcoming SNIa surveys, and in particular for the Large Synoptic Survey Telescope (LSST), for which uncertainties on the dark energy equation of state will be comparable to the effects reported here.
3874. Type Ibc SNe in disturbed galaxies
ID:
ivo://CDS.VizieR/J/ApJ/717/342
Title:
Type Ibc SNe in disturbed galaxies
Short Name:
J/ApJ/717/342
Date:
21 Oct 2021
Publisher:
CDS
Description:
We compare the radial locations of 178 core-collapse supernovae (CCSNe) to the R-band and H{alpha} light distributions of their host galaxies. When the galaxies are split into "disturbed" and "undisturbed" categories, a striking difference emerges. The disturbed galaxies have a central excess of CCSNe and this excess is almost completely dominated by supernovae of types Ib, Ic, and Ib/c, whereas type II supernovae dominate in all other environments. The difference cannot easily be explained by metallicity or extinction effects, and thus we propose that this is direct evidence for a stellar initial mass function that is strongly weighted toward high-mass stars, specifically in the central regions of disturbed galaxies.
3875. 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.
3876. 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.
3877. 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.
3878. 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.
3879. UBRI photometry of radio galaxies
ID:
ivo://CDS.VizieR/J/AJ/121/2381
Title:
UBRI photometry of radio galaxies
Short Name:
J/AJ/121/2381
Date:
21 Oct 2021
Publisher:
CDS
Description:
We describe a new estimate of the radio galaxy 1.4 GHz luminosity function and its evolution at intermediate redshifts (z~0.4). Photometric redshifts and color selection have been used to select B_J_<23.5 early-type galaxies from the Panoramic Deep Fields, a multicolor survey of two 25deg^2^ fields. Approximately 230 radio galaxies have then been selected by matching early-type galaxies with NVSS radio sources brighter than 5mJy. Estimates of the 1.4GHz luminosity function of radio galaxies measure significant evolution over the observed redshift range. For an {Omega}_M_=1 cosmology the evolution of the radio power is consistent with luminosity evolution where P(z)~P(0)(1+z)^K_L_^ and 3<K_L_<5. The observed evolution is similar to that observed for UVX and X-ray selected active galactic nuclei and is consistent with the same physical process being responsible for the optical and radio luminosity evolution of active galactic nuclei.
3880. UBR photometry of 39 elliptical galaxies
ID:
ivo://CDS.VizieR/J/AJ/100/1091
Title:
UBR photometry of 39 elliptical galaxies
Short Name:
J/AJ/100/1091
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have obtained U,B, and R CCD surface photometry for a sample of 39 elliptical galaxies. For each galaxy we have determined the surface brightness profile, U-R and B-R color profiles, and the ellipticity and position angle profiles, all as function of major axis radius, using a two-dimensional ellipse fitting program. In addition, we have derived the sin and cos(3.theta) and 4.theta terms that describe the high-order deviations of the B and R isophotes from ellipses. While it is very common for ellipticals to display measurable 3.theta and 4.theta terms, the amplitudes of these terms rarely exceed 0.5%. The isophotes of elliptical galaxies are very well characterized by ellipses. The surface brightness and color profiles are given to radii at which the error in the profile reaches 0.1 mag from the uncertainty in the brightness of the night sky. We have carried out a series of simulations of the effects of seeing on luminosity and ellipticity profiles, to determine the radius beyond which the errors in our data from seeing are less than 0.05 mag and 0.02 in ellipticity. Measurable effects of seeing extend to surprisingly large radii, as much as 5-10 seeing radii, depending upon the ellipticity of the galaxy and the form of the surface brightness profile. Ellipticity and position angle profiles are usually the same in all passbands with no indication that the contours of constant color are more or less flattened than the isophotes, i.e., the isochromes and isophotes have the same shapes, but the insensitivity of the ellipticity to differences between these properties makes this a weak argument. The high-order terms, particularly the 3.theta terms, appear to be sensitive diagnostics for the existence of dust in ellipticals. We find that all the galaxies in this sample either become bluer in B-R and U-R with increasing radius or are of constant color. Mean values for the logarithmic gradients in color are -0.09 mag/arcsec2 per dex in radius in B-R, and -0.20 mag/arcsec2 per dex in radius in U-R. These color changes are consistent with a decrease in the [Fe/H] of approximately 0.20 per decade in radius. Surprisingly, there is no correlation of color gradient with luminosity. It is striking, however, that the lowest luminosity galaxies in the sample (i.e., those with M(B) > -20) do not show any color gradients. They have boxy isophotes, and are also rotationally flattened. While these properties may be related to the fact that they are companions of larger ellipsoidal systems, it could provide an important clue to the formation of ellipticals. Low luminosity ellipticals that are not close companions to giant ellipticals need to be studied.