- ID:
- ivo://CDS.VizieR/J/A+A/638/A46
- Title:
- The XXL Survey. XLI. GMRT XXL-N 610MHz
- Short Name:
- J/A+A/638/A46
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study the space density evolution of active galactic nuclei (AGN) using the 610MHz radio survey of the XXL-North field, performed with the Giant Metrewave Radio Telescope (GMRT). The survey covers an area of 30.4deg^2^, with a beamsize of 6.5arcsec. The survey is divided into two parts, one covering an area of 11.9deg^2^ with 1{sigma} rms noise of 200uJy/beam and the other spanning 18.5deg^2^ with rms noise of 45uJy/beam. We extracted the catalog of radio components above 7. The catalog was cross-matched with a multi-wavelength catalog of the XXL-North field (covering about 80% of the radio XXL-North field) using a likelihood ratio method, which determines the counterparts based on their positions and their optical properties. The multi-component sources were matched visually with the aid of a computer code: Multi-Catalog Visual Cross-Matching (MCVCM). A flux density cut above 1mJy selects AGN hosts with a high purity in terms of star formation contamination based on the available source counts. After crossmatching and elimination of observational biases arising from survey incompleteness, the number of remaining sources was 1150. We constructed the rest-frame 1.4GHz radio luminosity functions of these sources using the maximum volume method. This survey allows us to probe luminosities of 23<~log(L1.4GHz[W/Hz])<~28 up to redshifts of z~=2.1. Our results are consistent with the results from the literature in which AGN are comprised of two differently evolving populations, where the high luminosity end of the luminosity functions evolves more strongly than the low-luminosity end.
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Search Results
- ID:
- ivo://CDS.VizieR/J/ApJ/750/97
- Title:
- The yellow and red supergiants of M33
- Short Name:
- J/ApJ/750/97
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Yellow and red supergiants are evolved massive stars whose numbers and locations on the Hertzsprung-Russell (H-R) diagram can provide a stringent test for models of massive star evolution. Previous studies have found large discrepancies between the relative number of yellow supergiants (YSGs) observed as a function of mass and those predicted by evolutionary models, while a disagreement between the predicted and observed locations of red supergiants (RSGs) on the H-R diagram was only recently resolved. Here, we extend these studies by examining the YSG and RSG populations of M33. Unfortunately, identifying these stars is difficult as this portion of the color-magnitude diagram is heavily contaminated by foreground dwarfs. We identify the RSGs through a combination of radial velocities and a two-color surface gravity discriminant, and after re-characterizing the rotation curve of M33 with our newly selected RSGs, we identify the YSGs through a combination of radial velocities and the strength of the OI{lambda}7774 triplet. We examine ~1300 spectra in total and identify 121 YSGs (a sample that is unbiased in luminosity above log(L/L_{sun}_)~4.8) and 189 RSGs. After placing these objects on the H-R diagram, we find that the latest generation of Geneva evolutionary tracks shows excellent agreement with the observed locations of our RSGs and YSGs, the observed relative number of YSGs with mass, and the observed RSG upper mass limit.
- ID:
- ivo://CDS.VizieR/J/ApJS/184/218
- Title:
- The zCOSMOS 10k-bright spectroscopic sample
- Short Name:
- J/ApJS/184/218
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present spectroscopic redshifts of a large sample of galaxies with I_AB_<22.5 in the COSMOS field, measured from spectra of 10644 objects that have been obtained in the first two years of observations in the zCOSMOS-bright redshift survey. These include a statistically complete subset of 10109 objects. The average accuracy of individual redshifts is 110km/s, independent of redshift. The reliability of individual redshifts is described by a Confidence Class that has been empirically calibrated through repeat spectroscopic observations of over 600 galaxies. There is very good agreement between spectroscopic and photometric redshifts for the most secure Confidence Classes. For the less secure Confidence Classes, there is a good correspondence between the fraction of objects with a consistent photometric redshift and the spectroscopic repeatability, suggesting that the photometric redshifts can be used to indicate which of the less secure spectroscopic redshifts are likely right and which are probably wrong, and to give an indication of the nature of objects for which we failed to determine a redshift. Using this approach, we can construct a spectroscopic sample that is 99% reliable and which is 88% complete in the sample as a whole, and 95% complete in the redshift range 0.5<z<0.8. The luminosity and mass completeness levels of the zCOSMOS-bright sample of galaxies is also discussed.
- ID:
- ivo://CDS.VizieR/VII/155
- Title:
- Third Reference Cat. of Bright Galaxies (RC3)
- Short Name:
- VII/155
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The University of Texas has revised its third edition of its catalogue of bright galaxies. This not only contains many more entries than the second edition (23,022) but substantially more information for each entry.
- ID:
- ivo://CDS.VizieR/J/ApJ/857/144
- Title:
- Tidal features from RESOLVE survey & DECaLS images
- Short Name:
- J/ApJ/857/144
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study tidal features around galaxies in the REsolved Spectroscopy Of a Local VolumE (RESOLVE) survey. Our sample consists of 1048 RESOLVE galaxies that overlap with the DECam Legacy Survey, which reaches an r-band 3{sigma} depth of ~27.9mag/arcsec^2^ for a 100arcsec^2^ feature. Images were masked, smoothed, and inspected for tidal features such as streams, shells, or tails/arms. We find tidal features in 17+/-2% of our galaxies, setting a lower limit on the true frequency. The frequency of tidal features in the gas-poor (gas-to-stellar mass ratio <0.1) subsample is lower than in the gas-rich subsample (13+/-3% versus 19+/-2%). Within the gas-poor subsample, galaxies with tidal features have higher stellar and halo masses, ~3x closer distances to nearest neighbors (in the same group), and possibly fewer group members at fixed halo mass than galaxies without tidal features, but similar specific star formation rates. These results suggest tidal features in gas-poor galaxies are typically streams/shells from dry mergers or satellite disruption. In contrast, the presence of tidal features around gas-rich galaxies does not correlate with stellar or halo mass, suggesting these tidal features are often tails/arms from resonant interactions. Similar to tidal features in gas-poor galaxies, tidal features in gas-rich galaxies imply 1.7x closer nearest neighbors in the same group; however, they are associated with diskier morphologies, higher star formation rates, and higher gas content. In addition to interactions with known neighbors, we suggest that tidal features in gas-rich galaxies may arise from accretion of cosmic gas and/or gas-rich satellites below the survey limit.
- ID:
- ivo://CDS.VizieR/J/AJ/130/2647
- Title:
- Tidal features of 126 nearby red galaxies
- Short Name:
- J/AJ/130/2647
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a study of tidal debris associated with 126 nearby red galaxies, selected from the 1.2{deg}^2^ Multiwavelength Survey by Yale-Chile (MUSYC, Cat. <J/ApJS/162/1>) and the 9.3{deg}^2^ NOAO Deep Wide-Field Survey (Jannuzi & Dey, 1999ASPC..191..111J). In the full sample, 67 galaxies (53%) show morphological signatures of tidal interactions consisting of broad fans of stars, tails, and other asymmetries at very faint surface brightness levels. When restricting the sample to the 86 bulge-dominated early-type galaxies, the fraction of tidally disturbed galaxies rises to 71%, which implies that for every "normal" undisturbed elliptical there are two that show clear signs of interactions. The tidal features are red and smooth and often extend over >50kpc.
- ID:
- ivo://CDS.VizieR/J/AJ/127/3121
- Title:
- TKRS catalog of GOODS-North Field
- Short Name:
- J/AJ/127/3121
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the results of an extensive imaging and spectroscopic survey in the Great Observatories Origins Deep Survey (GOODS)-North field completed using DEIMOS on the Keck II telescope. Observations of 2018 targets in a magnitude-limited sample of 2911 objects to R_AB_=24.4 yield secure redshifts for a sample of 1440 galaxies and active galactic nuclei (AGNs) plus 96 stars. In addition to redshifts and associated quality assessments, our catalog also includes photometric and astrometric measurements for all targets detected in our R-band imaging survey of the GOODS-North region.
- ID:
- ivo://CDS.VizieR/J/ApJ/653/1027
- Title:
- TKRS/GOODS-N Field galaxies
- Short Name:
- J/ApJ/653/1027
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present kinematic measurements of a large sample of galaxies from the Team Keck Redshift Survey in the GOODS-N field. We measure line-of-sight velocity dispersions from integrated emission for 1089 galaxies with median redshift 0.637 and spatially resolved kinematics for a subsample of 380 galaxies. This is the largest sample of galaxies to z~1 with kinematics to date and allows us to measure kinematic properties without morphological pre-selection. Emission-line widths provide a dynamical measurement for the bulk of blue galaxies. To fit the spatially resolved kinematics, we construct models that fit both line-of-sight rotation amplitude and velocity dispersion. Integrated line width correlates well with a combination of the velocity gradient and dispersion and is a robust measure of galaxy kinematics.
- ID:
- ivo://CDS.VizieR/J/A+A/656/A99
- Title:
- Tomography with Magnification Bias
- Short Name:
- J/A+A/656/A99
- Date:
- 21 Mar 2022 07:10:35
- Publisher:
- CDS
- Description:
- High-z submillimetre galaxies can be used as a background sample for gravitational lensing studies thanks to their magnification bias. In particular, the magnification bias can be exploited in order to constrain the free parameters of a halo occupation distribution (HOD) model and some of the main cosmological parameters. A pseudo-tomographic analysis shows that the tomographic approach should improve the parameter estimation. In this work the magnification bias has been evaluated as cosmological tool in a tomographic set up. The cross-correlation function (CCF) data have been used to jointly constrain the astrophysical parameters M_min_, M_1_ and {alpha} in each one of the selected redshift bins, as well as the cosmological parameter {Omega}_M_, {sigma}_8_ and H_0_ for the lambda cold dark matter ({Lambda}CMD). Moreover, we explore the possible time evolution of the dark energy density introducing the {omaga}_0_ and {omage}_a_ parameters in the joint analysis ({omega}_0_CDM and {omega}_0_{omega}_a_CDM). The CCF was measured between a foreground spectroscopic sample of Galaxy And Mass Assembly galaxies and a background sample of Herschel Astrophysical Terahertz Large Area Survey (H-ATLAS) galaxies. The foreground sample was divided into four redshift bins (0.1-0.2, 0.2-0.3, 0.3-0.5, and 0.5-0.8) and the sample of H-ATLAS galaxies has photometric redshifts >1.2. The CCF was modelled using a halo model description that depends on HOD and cosmological parameters. Then a Markov chain Monte Carlo method was used to estimate the parameters for different cases. For the {Lambda}CDM model the analysis yields a maximum posterior value at 0.26 with [0.17, 0.41] 68% C.I. for {Omega}_M_ and at 0.87 with [0.75, 1] 68% C.I. for {sigma}_8_. With our current results H_0_ is not yet constrained. With a more general {omega}_0_CDM model, the constraints on {Omega}_M_ and {sigma}_8_ are similar, but we found a maximum posterior value for {omega}_0_ at -1 with [-1.56, -0.47] 68% C.I. In the {omega}_0_{omega}_a_CDM model, the results are -1.09 with [-1.72, -0.66] 68% C.I. for {omega}_0_ and -0.19 with [-1.88, 1.48] 68% C.I. for {omega}_a_. The results on Mmin show a trend towards higher values at higher redshift confirming recent findings. The tomographic analysis presented in this work improves the constraints in the {sigma}_8_-{Omega}_M_ plane with respect to previous findings exploiting the magnification bias and it confirms that magnification bias results do not show the degeneracy found with cosmic shear measurements. Moreover, related to dark energy, we found a trend of higher {omega}_0_ values for lower H_0_ values.
- ID:
- ivo://CDS.VizieR/J/AJ/157/194
- Title:
- Total ALFALFA H I fluxes for extended sources
- Short Name:
- J/AJ/157/194
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A procedure is presented to improve on measurement of total H I fluxes for extended sources in the Arecibo Legacy Fast Arecibo L-band Feed Array (ALFALFA) survey of neutral hydrogen sources in the nearby universe. A number of tests of the procedure are detailed, and we verify that we recover all of the flux measured with much larger telescope beams. Total fluxes are reported for all sources (1) exceeding 10 Jy km/s in the {alpha}.100 catalog (Haynes et al. 2018ApJ...861...49H), or (2) with Uppsala General Catalog (Cat. VII/26) diameters 3.0 arcmin or more, or (3) ALFALFA pipeline isophotal ellipse area more than 3.0 times the Arecibo beam. Total fluxes are also provided for a number of confused pairs and small groups including one or more of those high-flux sources. These data should be of use in baryonic Tully-Fisher studies and other applications where the measurement of the total reservoir of neutral atomic gas is important.
