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1121. Galaxies as tracers of the circumgalactic gas
ID:
ivo://CDS.VizieR/J/ApJ/716/1514
Title:
Galaxies as tracers of the circumgalactic gas
Short Name:
J/ApJ/716/1514
Date:
21 Oct 2021
Publisher:
CDS
Description:
The circumgalactic medium (CGM) around galaxies is believed to record various forms of galaxy feedback and contain a significant portion of the "missing baryons" of individual dark matter halos. However, clear observational evidence for the existence of the hot CGM is still absent. We use intervening galaxies along 12 background active galactic nuclei (AGNs) as tracers to search for X-ray absorption lines produced in the corresponding CGM. Stacking Chandra grating observations with respect to galaxy groups and different luminosities of these intervening galaxies, we obtain spectra with signal-to-noise ratios of 46-72 per 20m{AA} spectral bin at the expected OVIIK{alpha} line. We find no detectable absorption lines of CVI, NVII, OVII, OVIII, or NeIX. The high spectral quality allows us to tightly constrain upper limits to the corresponding ionic column densities (in particular log[N_OVII_(cm^-2^)]<=14.2-14.8). These nondetections are inconsistent with the Local Group hypothesis of the X-ray absorption lines at z~0 commonly observed in the spectra of AGNs. These results indicate that the putative CGM in the temperature range of 10^5.5^-10^6.3^K may not be able to account for the missing baryons unless the metallicity is less than 10% solar.
1122. Galaxies at 1.4<~z<~3.0 in GOODS-North Field
ID:
ivo://CDS.VizieR/J/ApJ/653/1004
Title:
Galaxies at 1.4<~z<~3.0 in GOODS-North Field
Short Name:
J/ApJ/653/1004
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of a spectroscopic survey with LRIS-B on Keck of more than 280 star-forming galaxies and AGNs at redshifts 1.4~<z~<3.0 in the GOODS-N field. Candidates are selected by their UnGR colors using the "BM/BX" criteria to target redshift 1.4~<z~<2.5 galaxies and the LBG criteria to target redshift z~3 galaxies; combined these samples account for ~25%-30% of the R and Ks band counts to R=25.5 and Ks(AB)=24.4, respectively. The 212 BM/BX galaxies and 74 LBGs constitute the largest spectroscopic sample of galaxies at z>1.4 in GOODS-N. Extensive multiwavelength data allow us to investigate the stellar populations, stellar masses, bolometric luminosities (Lbol), and extinction z~2 of galaxies. Deep Chandra and Spitzer data indicate that the sample includes galaxies with a wide range in Lbol (~10^10^ to >10^12^L_{sun}_) and 4 orders of magnitude in dust obscuration (Lbol/LUV).
1123. Galaxies behind Southern Milky Way
ID:
ivo://CDS.VizieR/J/A+AS/141/123
Title:
Galaxies behind Southern Milky Way
Short Name:
J/A+AS/141/123
Date:
21 Oct 2021
Publisher:
CDS
Description:
A deep optical galaxy search in the southern Milky Way - aimed at reducing the width of the Zone of Avoidance - revealed 3279 galaxy candidates on the IIIaJ film copies of the ESO/SRC survey above the diameter limit of D greater than approximately 0.2 arcmin. Only 112 (3.4%) were previously catalogued. The surveyed region (266<l<296 and -10<b<+8) lies in the extension of the Hydra and Antlia clusters. Optical properties of the unveiled galaxies such as positions, diameters, magnitudes, morphological types are given in Table 1. Cross-identifications with the IRAS PSC (Cat. <II/125>) are given in Table 2.
1124. Galaxies behind Southern Milky Way. II.
ID:
ivo://CDS.VizieR/J/A+A/380/441
Title:
Galaxies behind Southern Milky Way. II.
Short Name:
J/A+A/380/441
Date:
21 Oct 2021
Publisher:
CDS
Description:
In this second paper of the catalogue series of galaxies behind the southern Milky Way, we report on the deep optical galaxy search in the Crux region (289{deg}<~l<~318{deg} and -10{deg}<~b<~10{deg}) and the Great Attractor region (316{deg}<~l<~338{deg} and -10{deg}<~b<~10{deg}). The galaxy catalogues are presented, a brief description of the galaxy search given, as well as a discussion on the distribution and characteristics of the uncovered galaxies. A total of 8183 galaxies with major diameters D>~0.2 arcmin were identified in this ~850 square degree area: 3759 galaxies in the Crux region and 4423 galaxies in the Great Attractor region. Of the 8183 galaxies, 229 (2.8%) were catalogued before in the optical (3 in radio) and 251 galaxies have a reliable (159), or likely (92) cross-identification in the IRAS Point Source Catalogue (3.1%). A number of prominent overdensities and filaments of galaxies are identified. They are not correlated with the Galactic foreground extinction and hence indicative of extragalactic large-scale structures. Redshifts obtained at the South African Astronomical Observatory (SAAO) for 518 of the newly catalogued galaxies in the Crux and Great Attractor regions (Fairall et al., 1998, Cat. <J/A+AS/127/463>; Woudt et al., 1999, Cat. <J/A+A/352/39>) confirm distinct voids and clusters in the area here surveyed. With this optical galaxy search, we have reduced the width of the optical `Zone of Avoidance' for galaxies with extinction-corrected diameters larger than 1.3' from extinction levels A_B>~1.0mag to A_B>~3.0mag: the remaining optical Zone of Avoidance is now limited by |b|<~3{deg} (see Fig. 16).
1125. Galaxies Behind the Milky Way
ID:
ivo://CDS.VizieR/VII/209A
Title:
Galaxies Behind the Milky Way
Short Name:
VII/209A
Date:
21 Oct 2021
Publisher:
CDS
Description:
This catalogue gathers the searches for galaxies of apparent size greater than 0.1mm (6.7") behind the Milky Way from photographic surveys in the near infrared. The five volumes cover the galactic longitude ranges -7 to +68{deg}, and 210 to 250{deg}.
1126. Galaxies Chemical and photometric evolution models
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.
1127. galaxies 2D phot. decompositions in SDSS-DR7
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.
1128. Galaxies >~6 from the Hubble Frontier Fields
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.
1129. 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.
1130. Galaxies in Fornax Cluster and five nearby groups
ID:
ivo://CDS.VizieR/VII/180
Title:
Galaxies in Fornax Cluster and five nearby groups
Short Name:
VII/180
Date:
21 Oct 2021
Publisher:
CDS
Description:
This catalog represents the combination of results published in two papers: Ferguson, H.C. 1989 A.J. 98, 367 (Paper II) and Ferguson, H.C. and Sandage, A. 1990 A.J. 100, 1 (Paper III). See the Historical Notes section below. Please note that the data from Paper II were previously archived as catalog VII/160. This catalog supersedes that earlier dataset. The following paragraphs describe the data included from the two papers. (Paper II) This paper presents a catalog of 2678 galaxies within an area of nearly 40 deg^2^ centered on the Fornax Cluster at {alpha}=3h35m and {delta}=-35.7deg. The data have been obtained from visual inspection of 26 deep large-scale (10.9arcsec/mm) plates taken with the du Pont 2.5m reflector at the Las Campanas Observatory, and from digital photometry of an ESO/SRC blue survey plate covering roughly the same area of the sky. The catalog is essentially diameter limited, with a limiting diameter of 17arcsec at an isophoto of B_T_ =26.5. Within this survey region, the catalog includes 340 likely cluster members and 2338 likely background galaxies. For cluster members, this listing should be complete to B_T_=18 (corresponding to M_BT_=13.0, assuming a distance modulus of m-M=31.9) and contains likely members down to B_T_=20. Cluster membership is for the most part based on galaxy morphology. By virtue of their low surface brightness, dwarf galaxies in the cluster can be distinguished with a high degree of certainty from background galaxies. Radial velocities are included for 89 galaxies in the survey, providing a reliable indicator of membership in these cases. As additional support for our rejection of background galaxies, we model the spatial distribution of various types of galaxies as the sum of a King model cluster component superimposed on a uniform background. Using maximum-likelyhood fits to these spatial distributions, we find a core radius of 0.7deg. for a King model fit to the cluster, and show that there are few, if any, cluster members contained in the sample of background galaxiesBD (Paper III) Five nearby groups of galaxies have been surveyed using large-scale plates from the 2.5 m duPont Telescope at Las Campanas Observatory. Catalogs of galaxies brighter than B_T_ ~ 20 are presented for the Leo, Dorado, NGC 1400, NGC 5044, and Antlia groups. A total of 1044 galaxies are included, from visual inspection of 14 plates, covering 31deg square. Galaxies have been classified in the extended Hubble system, and group memberships have been assigned based on velocity (where available) and morphology. About half the galaxies listed are likely members of one of the nearby groups. The catalogs are complete to B_T_ ~ 18, although the completeness limits vary slightly from group to group. Based on King model fits to the surface density profiles, the core radii of the groups range from 0.3 to 1 Mpc, and central densities range from 120 to 1900 galaxies Mpc^-3^ brighter than M_BT_ = -12.5. Dynamical analysis indicates that all of the groups of likely to be gravitationally bound.