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3671. The central black hole in NGC 4414
ID:
ivo://CDS.VizieR/J/A+A/597/A18
Title:
The central black hole in NGC 4414
Short Name:
J/A+A/597/A18
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present our mass estimate of the central black hole in the isolated spiral galaxy NGC 4414. Using natural guide star adaptive optics assisted observations with the Gemini Near-Infrared Integral Field Spectrometer (NIFS) and the natural seeing Gemini Multi-Object Spectrographs-North (GMOS), we derived two-dimensional stellar kinematic maps of NGC 4414 covering the central 1.5-arcsec and 10-arcsec, respectively, at a NIFS spatial resolution of 0.13-arcsec. The kinematic maps reveal a regular rotation pattern and a central velocity dispersion dip down to around 105km/s. We constructed dynamical methods using two different methods: Jeans anisotropic dynamical modeling and axisymmetric Schwarzschild modeling. Both modeling methods give consistent results, but we cannot constrain the lower mass limit and only measure an upper limit for the black hole mass of M_bh_=1.56x10^6^M_{sun}_ (at 3{sigma{ level) which is at least 1{sigma} below the recent Mbh-sigma_e relations. Further tests with dark matter, mass-to-light ratio variation and different light models confirm that our results are not dominated by uncertainties. The derived upper limit mass is not only below the Mbh-sigma_e relation, but is also five times lower than the lower limit black hole mass anticipated from the resolution limit of the sphere of influence. This proves that via high quality integral field data we are now able to push black hole measurements down to at least five times less than the resolution limit.
3672. The central Fornax Cluster. I. Galaxy photometry
ID:
ivo://CDS.VizieR/J/A+AS/134/59
Title:
The central Fornax Cluster. I. Galaxy photometry
Short Name:
J/A+AS/134/59
Date:
21 Oct 2021
Publisher:
CDS
Description:
In this paper, a photometric catalog is presented of V and I photometry of galaxies in the central regions of the Fornax galaxy cluster. Our 11 CCD fields cover 0.17 square degrees in total. The limiting surface brightness is around 24mag/arcsec^2^, similar to that of Ferguson's (1989, Cat. <VII/180>) catalog, whereas our limiting total magnitude is around V=22mag, about two magnitudes fainter. The photometric properties of more than 870 objects are presented as a catalog (Appendix A). The properties and fit parameters of the surface brightness profiles for a sub-sample are presented in a second catalog (Appendix B). Four new dwarf galaxies are added to Ferguson's catalog. However, we confirm that the dwarf galaxies in Fornax follow a similar surface brightness -- magnitude relation as the Local Group dwarfs. They also follow the color (metallicity) -- magnitude relation seen in other galaxy clusters. A formerly suspected excess of dwarf galaxies surrounding the central giant cD galaxy NGC 1399 can be explained by the superposition of a background cluster at z=0.11 (Hilker et al. 1998, Cat. <J/A+AS/134/75>, Paper II in this series).
3673. The CfA2S catalog
ID:
ivo://CDS.VizieR/J/ApJS/121/287
Title:
The CfA2S catalog
Short Name:
J/ApJS/121/287
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present redshifts for a sample of 4391 galaxies with magnitude m_B(0)_<=15.5 covering 20h<=RA<=4h in right ascension and -2.5{deg}<=DE<=90{deg} in declination. This sample is complete for all galaxies in the merge of the Zwicky et al. and Nilson catalogs in the south Galactic cap. Redshifts for 2964 of these were measured as part of the second CfA Redshift Survey. The data reveal large voids in the foreground and background of the Perseus-Pisces Supercluster. The largest of these voids lies at a mean velocity ~8000km/s, has diameter ~5000km/s, and is enclosed by a complex of dense structures. The large structure known as the Perseus-Pisces Supercluster forms the near side of this complex. On the far side of this large void, at a mean velocity ~12000km/s, there is another coherent dense wall. The structures in this survey support the view that galaxies generally lie on surfaces surrounding or nearly surrounding low-density regions or voids.
3674. The CGS. IV. Elliptical galaxies colors
ID:
ivo://CDS.VizieR/J/ApJ/821/114
Title:
The CGS. IV. Elliptical galaxies colors
Short Name:
J/ApJ/821/114
Date:
21 Oct 2021
Publisher:
CDS
Description:
Many recent observations and numerical simulations suggest that nearby massive, early-type galaxies (ETGs) were formed through a "two-phase" process. In the proposed second phase, the extended stellar envelope was accumulated through many dry mergers. However, details of the past merger history of present-day ellipticals, such as the typical merger mass ratio, are difficult to constrain observationally. Within the context and assumptions of the two-phase formation scenario, we propose a straightforward method, using photometric data alone, to estimate the average mass ratio of mergers that contributed to the build-up of massive elliptical galaxies. We study a sample of nearby massive elliptical galaxies selected from the Carnegie-Irvine Galaxy Survey, using two-dimensional analysis to decompose their light distribution into an inner, denser component plus an extended, outer envelope, each having a different optical color. The combination of these two substructures accurately recovers the negative color gradient exhibited by the galaxy as whole. The color difference between the two components (<{Delta}(B-V)>~0.10mag; <{Delta}(B-R)>~0.14mag), based on the slope of the M*-color relation for nearby ETGs, can be translated into an estimate of the average mass ratio of the mergers. The rough estimate, 1:5 to 1:10, is consistent with the expectation of the two-phase formation scenario, suggesting that minor mergers were largely responsible for building up the outer stellar envelopes of present-day massive ellipticals. With the help of accurate photometry, large sample sizes and more choices of colors promised by ongoing and future surveys, the approach proposed here can provide more insights into the growth of massive galaxies during the last few Gyr.
3675. The CGS. IX. R-band single-Sersic fits to ellipticals
ID:
ivo://CDS.VizieR/J/ApJS/247/20
Title:
The CGS. IX. R-band single-Sersic fits to ellipticals
Short Name:
J/ApJS/247/20
Date:
21 Oct 2021
Publisher:
CDS
Description:
We study the statistical properties of 320 bulges of disk galaxies in the Carnegie-Irvine Galaxy Survey, using robust structural parameters of galaxies derived from image fitting. We apply the Kormendy relation to classify classical and pseudo bulges and characterize the bulge dichotomy with respect to the structural properties of the bulges and the physical properties of the host galaxies. We confirm previous findings that pseudo bulges on average have smaller Sersic indices, lower bulge-to-total ratios, and fainter surface brightnesses than classical bulges. Our sizable sample statistically shows that pseudo bulges are more intrinsically flattened than classical bulges. Pseudo bulges are most frequent (incidence >~80%) in late-type spirals (later than Sc). Our measurements support the picture in which pseudo bulges arose from star formation induced by inflowing gas, while classical bulges were born out of violent processes such as mergers and coalescence of clumps. We reveal differences with the literature that warrant attention: (1) the bimodal distribution of Sersic indices presented by previous studies is not reproduced in our study; (2) classical and pseudo bulges have similar relative bulge sizes; and (3) the pseudo bulge fraction is considerably smaller in early-type disks than reported in previous studies based on one-dimensional surface brightness profile fitting. We attribute these differences to our improved image quality, more robust bulge-to-disk decomposition technique, and to the different classification criteria that we applied. Moreover, we find that barred galaxies do not host more pseudo bulges or more prominent pseudo bulges than unbarred galaxies. Various implications of these findings are discussed.
3676. The CGS. VIII. R-band images of disk galaxies
ID:
ivo://CDS.VizieR/J/ApJS/244/34
Title:
The CGS. VIII. R-band images of disk galaxies
Short Name:
J/ApJS/244/34
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present multicomponent decomposition of high-quality R-band images of 320 disk galaxies from the Carnegie-Irvine Galaxy Survey. In addition to bulges and disks, we successfully model nuclei, bars, disk breaks, nuclear/inner lenses, and inner rings. Our modeling strategy treats nuclear rings and nuclear bars as part of the bulge component, while other features such as spiral arms, outer lenses, and outer rings are omitted from the fits because they are not crucial for accurate bulge measurements. The error budget of bulge parameters includes the uncertainties from sky-level measurements and model assumptions. Comparison with multicomponent decomposition from the Spitzer Survey of Stellar Structure in Galaxies reveals broad agreement for the majority of the overlapping galaxies, but for a considerable fraction of galaxies there are significant differences in bulge parameters caused by different strategies in model construction. We confirm that on average bulge prominence decreases from early- to late-type disk galaxies, although the large scatter of bulge-to-total ratios in each morphological bin limits the application of Hubble type as an accurate predictor of bulge-to-total ratio. In contrast with previous studies claiming that barred galaxies host weaker bulges, we find that barred and unbarred spiral galaxies have similar bulge prominence.
3677. The Chandra COSMOS survey. III.
ID:
ivo://CDS.VizieR/J/ApJS/201/30
Title:
The Chandra COSMOS survey. III.
Short Name:
J/ApJS/201/30
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Chandra COSMOS Survey (C-COSMOS) is a large, 1.8Ms, Chandra program that has imaged the central 0.9deg^2^ of the COSMOS field down to limiting depths of 1.9x10^-16^erg/cm^2^/s in the soft (0.5-2keV) band, 7.3x10^-16^erg/cm^2^/s in the hard (2-10keV) band, and 5.7x10^-16^erg/cm^2^/s in the full (0.5-10keV) band. In this paper we report the i, K, and 3.6um identifications of the 1761 X-ray point sources. We use the likelihood ratio technique to derive the association of optical/infrared counterparts for 97% of the X-ray sources. For most of the remaining 3%, the presence of multiple counterparts or the faintness of the possible counterpart prevented a unique association. For only 10 X-ray sources we were not able to associate a counterpart, mostly due to the presence of a very bright field source close by. Only two sources are truly empty fields. The full catalog, including spectroscopic and photometric redshifts and classification described here in detail, is available online.
3678. The CNOC2 survey. I.
ID:
ivo://CDS.VizieR/J/ApJS/129/475
Title:
The CNOC2 survey. I.
Short Name:
J/ApJS/129/475
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Canadian Network for Observational Cosmology Field Galaxy Redshift Survey (CNOC2) obtained spectroscopic redshifts for about 6200 galaxies to a nominal limit of R=21.5. The survey area of about 1.5 square degrees was spread over four patches on the sky. This catalog presents photometry and redshifts for all galaxies in the CNOC2 0223+00 Patch (area of 1409 square arcminutes). A future paper will provide catalogs for the other three patches.
3679. The COSMOS2015 catalog
ID:
ivo://CDS.VizieR/J/ApJS/224/24
Title:
The COSMOS2015 catalog
Short Name:
J/ApJS/224/24
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the COSMOS2015 catalog, which contains precise photometric redshifts and stellar masses for more than half a million objects over the 2deg^2^ COSMOS field. Including new YJHKs images from the UltraVISTA-DR2 survey, Y-band images from Subaru/Hyper-Suprime-Cam, and infrared data from the Spitzer Large Area Survey with the Hyper-Suprime-Cam (SPLASH) Spitzer legacy program, this near-infrared-selected catalog is highly optimized for the study of galaxy evolution and environments in the early universe. To maximize catalog completeness for bluer objects and at higher redshifts, objects have been detected on a {chi}^2^ sum of the YJHKs and z^++^ images. The catalog contains ~6x10^5^ objects in the 1.5deg^2^ UltraVISTA-DR2 region and ~1.5x10^5^ objects are detected in the "ultra-deep stripes" (0.62deg^2^) at Ks<=24.7 (3{sigma}, 3", AB (AB) magnitude). Through a comparison with the zCOSMOS-bright spectroscopic redshifts, we measure a photometric redshift precision of {sigma}_{Delta}z/(1+zs)_=0.007 and a catastrophic failure fraction of {eta}=0.5%. At 3<z<6 , using the unique database of spectroscopic redshifts in COSMOS, we find {sigma}_{Delta}z/(1+zs)_=0.021 and {eta}=13.2% . The deepest regions reach a 90% completeness limit of 10^10^M_{sun}_ to z=4. Detailed comparisons of the color distributions, number counts, and clustering show excellent agreement with the literature in the same mass ranges. COSMOS2015 represents a unique, publicly available, valuable resource with which to investigate the evolution of galaxies within their environment back to the earliest stages of the history of the universe.
3680. The C3R2 survey: DR2 new spectroscopic redshifts
ID:
ivo://CDS.VizieR/J/ApJ/877/81
Title:
The C3R2 survey: DR2 new spectroscopic redshifts
Short Name:
J/ApJ/877/81
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Complete Calibration of the Color-Redshift Relation (C3R2) survey is a multi-institution, multi-instrument survey that aims to map the empirical relation of galaxy color to redshift to i~24.5 (AB), thereby providing a firm foundation for weak lensing cosmology with the Stage IV dark energy missions Euclid and WFIRST. Here we present 3171 new spectroscopic redshifts obtained in the 2016B and 2017A semesters with a combination of DEIMOS, LRIS, and MOSFIRE on the Keck telescopes. The observations come from all of the Keck partners: Caltech, NASA, the University of Hawaii, and the University of California. Combined with the 1283 redshifts published in DR1, the C3R2 survey has now obtained and published 4454 high-quality galaxy redshifts. We discuss updates to the survey design and provide a catalog of photometric and spectroscopic data. Initial tests of the calibration method performance are given, indicating that the sample, once completed and combined with extensive data collected by other spectroscopic surveys, should allow us to meet the cosmology requirements for Euclid, and make significant headway toward solving the problem for WFIRST. We use the full spectroscopic sample to demonstrate that galaxy brightness is weakly correlated with redshift once a galaxy is localized in the Euclid or WFIRST color space, with potentially important implications for the spectroscopy needed to calibrate redshifts for faint WFIRST and LSST sources.