- ID:
- ivo://CDS.VizieR/VI/147
- Title:
- Galaxies Chemical and photometric evolution models
- Short Name:
- VI/147
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We summarize the updated set of multiphase chemical evolution models performed with 44 theoretical radial mass initial distributions and 10 possible values of efficiencies to form molecular clouds and stars. We present the results about the infall rate histories, the formation of the disk, and the evolution of the radial distributions of diffuse and molecular gas surface density, stellar profile, star formation rate surface density, and elemental abundances of C, N, O, and Fe, finding that the radial gradients for these elements begin steeper and flatten with increasing time or decreasing redshift, although the outer disks always show a certain flattening for all times. With the resulting star formation and enrichment histories, we calculate the spectral energy distributions (SEDs) for each radial region by using the ones for single stellar populations resulting from the evolutive synthesis model POPSTAR. With these SEDs we may compute finally the broad band magnitudes and colors radial distributions in the Johnson and in the SLOAN/SDSS systems which are the main result of this work. We present the evolution of these brightness and color profiles with the redshift.
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- ID:
- ivo://CDS.VizieR/J/MNRAS/446/3943
- Title:
- galaxies 2D phot. decompositions in SDSS-DR7
- Short Name:
- J/MNRAS/446/3943
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalogue of 2D, point spread function-corrected de Vacouleurs, Sersic, de Vacouleurs+Exponential, and Sersic+Exponential fits of ~7x10^5^ spectroscopically selected galaxies drawn from the Sloan Digital Sky Survey (SDSS) Data Release 7. Fits are performed for the SDSS r band utilizing the fitting routine galfit and analysis pipeline pymorph. We compare these fits to prior catalogues. Fits are analysed using a physically motivated flagging system. The flags suggest that more than 90 percent of two-component fits can be used for analysis. We show that the fits follow the expected behaviour for early and late galaxy types. The catalogues provide a robust set of structural and photometric parameters for future galaxy studies. We show that some biases remain in the measurements, e.g. the presence of bars significantly affect the bulge measurements although the bulge ellipticity may be used to separate barred and non-barred galaxies, and about 15 percent of bulges of two-component fits are also affected by resolution. The catalogues are available in electronic format. We also provide an interface for generating postage stamp images of the 2D model and residual as well as the 1D profile. These images can be generated for a user-uploaded list of galaxies on demand.
- ID:
- ivo://CDS.VizieR/J/ApJ/835/113
- Title:
- Galaxies >~6 from the Hubble Frontier Fields
- Short Name:
- J/ApJ/835/113
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report a new analysis of the Hubble Frontier Fields clusters Abell2744 and MACS 0416 using wavelet decomposition to remove the cluster light, enabling the detection of highly magnified (>50x) galaxies a factor of 10x fainter in luminosity than previous studies. We find 167 galaxies at z>~6, and with this sample we are able to characterize the UV luminosity function to M_UV_=-12.5 at z~6, -14 at z~7, and -15 at z~8. We find a steep faint-end slope ({alpha}< -2), and with our improved statistics at the faint end we reduce the fractional uncertainty on {alpha} to <2% at z~6-7 and 4% at z~8. We also investigate the systematic uncertainty due to the lens modeling by using every available lens model individually and comparing the results; this systematic fractional uncertainty on {alpha} is <4% at all redshifts. We now directly observe galaxies in the luminosity regime where some simulations predict a change in the faint-end slope of the luminosity function, yet our results provide statistically very strong evidence against any turnover in the luminosity range probed, more consistent with simulations in which stars form in lower-mass halos. Thus, we find strong support for the extension of the steep luminosity function to M_UV_=-13 at z>6, consistent with the number of faint galaxies needed to reionize the universe under standard assumptions.
2124. Galaxies in Abell 168
- ID:
- ivo://CDS.VizieR/J/AJ/111/42
- Title:
- Galaxies in Abell 168
- Short Name:
- J/AJ/111/42
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- V- and I- band CCD photometry of the central 0.18 square degree of Abell 168 was observed in November and December 1993 at the 1.05m Kiso Schmidt telescope (f/3.1). The CCD chip has 1000x1018 pixels, the pixel size is 0.752arcsec, giving a field of view of 12.0x12.7 arcmin. The total observed region was covered by 7 individual CCD fields. Note that some revisions were made by the author (TOMITA Akihiko) compared to the original publication.
- ID:
- ivo://CDS.VizieR/J/ApJS/78/1
- Title:
- Galaxies in 7 clusters 0.35<z<0.55
- Short Name:
- J/ApJS/78/1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present photometry and spectroscopy for seven deep fields containing distant clusters of galaxies with 0.35<z<0.55. Positions and photometric parameters, including r-magnitudes g-r and r-i colors, surface brightnesses, and photometric profile types are given for about 2000 galaxies. Low-resolution spectroscopy is obtained from which redshifts are determined for 289 objects, of which 190 are cluster members.
- ID:
- ivo://CDS.VizieR/J/other/AstBu/69.247
- Title:
- Galaxies in Lynx-Cancer void
- Short Name:
- J/other/AstBu/69
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this work we present the results of photometrical study of 85 objects from the updated sample of galaxies residing in the nearby Lynx-Cancer void. The images in filters u,g,r,i from the Sloan Digital Sky Survey database are used for photometry. The following model-independent parameters are obtained: integrated magnitudes and colours, effective radii and the respective surface brightnesses, optical and Holmberg radii. On results of the radial surface brightness profile analysis, their central values and scalelengths of model discs are derived. The colours of the outer parts of void galaxies are examined and compared to those of the model evolutionary tracks of the PEGASE2 package. This allowed to obtain estimates of the time since the epoch of star formation T_SF_. Among the latter group, the low-luminosity objects with M_B_>-13.2 dominate. The derived integrated absolute magnitudes and colours are used for galaxy stellar mass estimates. All available data on integrated galaxy HI fluxes are used to derive their parameter M(HI)/L_B_ and to estimate their gas mass-fraction. The small ~10% subgroup of the most gas-rich galaxies, with M(HI)/L_B_>2.5, shows gas mass-fractions reaching (94-99)%. Many of these objects also show atypically blue colours of their outer parts. To check possible statistical differences of void galaxy properties and galaxy samples formed with more general criteria, we compared the void sample galaxy parameters with those of 195 galaxies from the Equatorial Survey (ES), formed as a part of the blind HI survey HIPASS. In the common luminosity range (-18.5<M_g_<-13.5) the compared samples show similarity. The lowest luminosity void galaxies differ from the main ES sample. However, there are also ~7% faint so called 'inchoate' galaxies among ES sample with the elevated parameter M(HI)/L_B_, majority of which are situated far from massive neighbours and are probably the analogs of void galaxies.
- ID:
- ivo://CDS.VizieR/J/AJ/121/1840
- Title:
- Galaxies in Q0835+580 and Q1126+101 fields
- Short Name:
- J/AJ/121/1840
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have previously identified an excess population of predominantly red galaxies around a sample of 31 radio-loud quasars (RLQs) at 1<z<2. Here we show that these fields have a surface density of extremely red objects (EROs, with R-K>6) 2.7 times higher than the general field. Assuming these EROs are passively evolved galaxies at the quasar redshifts, they have characteristic luminosities of only ~L*. Only one of four RLQ fields has an excess of J-K-selected EROs with J-K>2.5; thus, those objects are mostly unrelated to the quasars. We also present new multiwavelength data and analyses on the fields of four of these quasars at z_q_~1.54, obtained to build more detailed pictures of the environments of these quasars and the galaxies within them.
- ID:
- ivo://CDS.VizieR/J/MNRAS/467/4220
- Title:
- Galaxies inside 120 arcsec of HE 0435-1223
- Short Name:
- J/MNRAS/467/4220
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Based on spectroscopy and multiband wide-field observations of the gravitationally lensed quasar HE 0435-1223, we determine the probability distribution function of the external convergence {kappa}_ext_ for this system. We measure the under/overdensity of the line of sight towards the lens system and compare it to the average line of sight throughout the Universe, determined by using the CFHTLenS (The Canada France Hawaii Lensing Survey) as a control field. Aiming to constrain {kappa}_ext_ as tightly as possible, we determine under/overdensities using various combinations of relevant informative weighting schemes for the galaxy counts, such as projected distance to the lens, redshift and stellar mass. We then convert the measured under/overdensities into a {kappa}_ext_ distribution, using ray-tracing through the Millennium Simulation. We explore several limiting magnitudes and apertures, and account for systematic and statistical uncertainties relevant to the quality of the observational data, which we further test through simulations. Our most robust estimate of {kappa}_ext_ has a median value {kappa}^med^_ext_=0.004 and a standard deviation {sigma}_{kappa}_=0.025. The measured {sigma}_{kappa}_ corresponds to 2.5 per cent relative uncertainty on the time delay distance, and hence the Hubble constant H_0_ inferred from this system. The median {kappa}^med^_ext_ value varies by ~0.005 with the adopted aperture radius, limiting magnitude and weighting scheme, as long as the latter incorporates galaxy number counts, the projected distance to the main lens and a prior on the external shear obtained from mass modelling. This corresponds to just ~0.5 per cent systematic impact on H_0_. The availability of a well-constrained {kappa}_ext_ makes HE 0435-1223 a valuable system for measuring cosmological parameters using strong gravitational lens time delays.
- ID:
- ivo://CDS.VizieR/J/A+A/406/593
- Title:
- Galaxies in Southern Bright Star Fields I.
- Short Name:
- J/A+A/406/593
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- As a prerequisite for cosmological studies using adaptive optics techniques, we have begun to identify and characterize faint sources in the vicinity of bright stars at high Galactic latitudes. The initial phase of this work has been a program of K_s_ imaging conducted with SOFI at the ESO NTT. From observations of 42 southern fields evenly divided between the spring and autumn skies, we have identified 391 additional stars and 1589 galaxies lying at separations <60" from candidate guide stars in the magnitude range 9.0<R<12.4. When analyzed as a "discrete deep field" with 131-arcmin^2^ area, our dataset gives galaxy number counts that agree with those derived previously over the range 16<K_s_<20.5. This consistency indicates that in the aggregate, our fields should be suitable for future statistical studies. We provide our source catalogue as a resource for users of large telescopes in the southern hemisphere.
- ID:
- ivo://CDS.VizieR/J/MNRAS/404/749
- Title:
- Galaxies in the field of B2108+213
- Short Name:
- J/MNRAS/404/749
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The gravitational lens system CLASS B2108+213 has two radio-loud lensed images separated by 4.56 arcsec. The relatively large image separation implies that the lensing is caused by a group of galaxies. In this paper, new optical imaging and spectroscopic data for the lensing galaxies of B2108+213 and the surrounding field galaxies are presented. These data are used to investigate the mass and composition of the lensing structure.
