- ID:
- ivo://CDS.VizieR/J/A+A/489/571
- Title:
- VRizK photometry of RDCSJ0910+54 cluster
- Short Name:
- J/A+A/489/571
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report on the environmental dependence of properties of galaxies around the RDCSJ0910+54 cluster at z=1.1. We obtained multi-band wide-field images of the cluster with Suprime-Cam and MOIRCS on Subaru and WFCAM on UKIRT. Also, an intensive spectroscopic campaign was carried out using LRIS on Keck and FOCAS on Subaru. We collected 161 spectra with secure redshifts, with which we calibrated a larger sample of photometric redshifts.
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Search Results
- ID:
- ivo://CDS.VizieR/J/AJ/122/714
- Title:
- VR photometry of Century Survey galaxies
- Short Name:
- J/AJ/122/714
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use 64{deg}^2^ of deep V and R CCD images to measure the local V- and R-band luminosity functions of galaxies. The V_0_<16.7 and R_0_<16.2 redshift samples contain 1255 and 1251 galaxies and are 98.1% and 98.2% complete, respectively.
4073. VSOP 5 GHz AGN Survey
- ID:
- ivo://CDS.VizieR/J/PASJ/52/997
- Title:
- VSOP 5 GHz AGN Survey
- Short Name:
- J/PASJ/52/997
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The VSOP mission is a Japanese-led project to image radio sources with sub-milliarcsec resolution by correlating the signal from the orbiting 8-m telescope, HALCA, with a global array of telescopes. Twenty- five percent of the scientific time of this mission is devoted to a survey of 402 bright, small-diameter extra-galactic radio sources at 5-GHz. The major goals of the VSOP Survey are statistical in nature: to determine the brightness temperature and approximate structure; to provide a source list for use with future space VLBI missions; and to compare radio properties with other data throughout the EM spectrum. This paper describes: the compilation of a complete list of radio sources associated with active galactic nuclei (AGN); the selection of the subsample of sources to be observed with VSOP; the extensive ground resources used for the Survey; the status of the observations as of 2000 July; the data-analysis methods; and several examples of results from the VSOP Survey. More detailed results from the full sample will be given in future papers.
- ID:
- ivo://CDS.VizieR/J/ApJS/131/95
- Title:
- VSOP 5 GHz continuum survey
- Short Name:
- J/ApJS/131/95
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have imaged with milliarcsecond resolution at 5 GHz 374 strong flat-spectrum radio sources north of declination -44{deg} using the VLBA in 1996 June. The source sample was compiled from the source list for the VLBI Space Observatory Programme (VSOP) Survey Program. About 250 of the sources observed with the VLBA had correlated flux densities >=0.3 Jy on the longest VLBA baseline and these sources are currently being observed with VSOP at 5 GHz. This paper presents the results from the VLBA prelaunch observations: the correlated flux density dependence with u-v distance; the contour display of the images; the model fit parameters for each radio component; and improved positions for 62 sources. Comparisons and extensive cross-referencing with other major VLBI surveys are also given.
- ID:
- ivo://CDS.VizieR/J/A+A/572/A41
- Title:
- VUDS Dicovery of a high-redshift protocluster
- Short Name:
- J/A+A/572/A41
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using new spectroscopic observations obtained as part of the VIMOS Ultra-Deep Survey (VUDS), we performed a systematic search for overdense environments in the early universe (z>2) and report here on the discovery of Cl J0227-0421, a massive protocluster at z=3.29. This protocluster is characterized by both the large overdensity of spectroscopically confirmed members, delta_gal=10.5+/-2.8, and a significant overdensity in photometric redshift members. The halo mass of this protocluster is estimated by a variety of methods to be ~3x10^14^M_{sun}_ at z~3.3, which, evolved to z=0 results in a halo mass rivaling or exceeding that of the Coma cluster. The properties of 19 spectroscopically confirmed member galaxies are compared with a large sample of VUDS/VVDS galaxies in lower density field environments at similar redshifts. We find tentative evidence for an excess of redder, brighter, and more massive galaxies within the confines of the protocluster relative to the field population, which suggests that we may be observing the beginning of environmentally induced quenching. The properties of these galaxies are investigated, including a discussion of the brightest protocluster galaxy, which appears to be undergoing vigorous coeval nuclear and starburst activity. The remaining member galaxies appear to have characteristics that are largely similar to the field population. Though we find weaker evidence of the suppression of the median star formation rates among and differences in the stacked spectra of member galaxies with respect to the field, we defer any conclusions about these trends to future work with the ensemble of protostructures that are found in the full VUDS sample.
- ID:
- ivo://CDS.VizieR/J/A+A/568/L8
- Title:
- VUDS extreme emission line 0.2<~z<~0.9 galaxies
- Short Name:
- J/A+A/568/L8
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the discovery of 31 low-luminosity (-14.5>~M_AB_(B)>~-18.8), extreme emission line galaxies (EELGs) at 0.2<~z<~0.9 identified by their unusually high rest-frame equivalent widths (100<=EW[OIII]<=1700{AA}) as part of the VIMOS Ultra Deep Survey (VUDS). VIMOS optical spectra of unprecedented sensitivity (I_AB_~25mag) along with multiwavelength photometry and HST imaging are used to investigate spectrophotometric properties of this unique sample and to explore, for the first time, the very low stellar mass end (M_*_<~10^8^M_{sun}_) of the luminosity-metallicity (LZR) and mass-metallicity (MZR) relations at z<1. Characterized by their extreme compactness (R_50_<1kpc), low stellar mass and enhanced specific star formation rates (sSFR=SFR/M_*_~10^-9^-10^-7^yr^-1^), the VUDS EELGs are blue dwarf galaxies likely experiencing the first stages of a vigorous galaxy-wide starburst. Using Te-sensitive direct and strong-line methods, we find that VUDS EELGs are low-metallicity (7.5<~12+log(O/H)<~8.3) galaxies with high ionization conditions (log(q_ion_)>~8cm/s), including at least three EELGs showing HeII{lambda}4686{AA} emission and four extremely metal-poor (<~10% solar) galaxies. The LZR and MZR followed by VUDS EELGs show relatively large scatter, being broadly consistent with the extrapolation toward low luminosity and mass from previous studies at similar redshift. However, we find evidence that galaxies with younger and more vigorous star formation --as characterized by their larger EWs, ionization and sSFR-- tend to be more metal poor at a given stellar mass.
- ID:
- ivo://CDS.VizieR/J/A+A/634/A97
- Title:
- VUDS UV and Ly{alpha} luminosity functions
- Short Name:
- J/A+A/634/A97
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The star formation rate density (SFRD) evolution presents an area of great interest in the studies of galaxy evolution and reionization. The current constraints of SFRD at z>5 are based on the rest-frame UV luminosity functions with the data from photometric surveys. The VIMOS UltraDeep Survey (VUDS) was designed to observe galaxies at redshifts up to ~6 and opened a window for measuring SFRD at z>5 from a spectroscopic sample with a well-controlled selection function. We establish a robust statistical description of the star-forming galaxy population at the end of cosmic HI reionization (5.0<=z<=6.6) from a large sample of 49 galaxies with spectroscopically confirmed redshifts. We determine the rest-frame UV and Ly{alpha} luminosity functions and use them to calculate SFRD at the median redshift of our sample z=5.6. We selected a sample of galaxies at 5.0<=z_spec_<=6.6 from the VUDS. We cleaned our sample from low redshift interlopers using ancillary photometric data. We identified galaxies with Ly{alpha} either in absorption or in emission, at variance with most spectroscopic samples in the literature where Ly{alpha} emitters (LAE) dominate. We determined luminosity functions using the 1/V_max_ method. The galaxies in this redshift range exhibit a large range in their properties. A fraction of our sample shows strong Ly{alpha} emission, while another fraction shows Ly{alpha} in absorption. UV-continuum slopes vary with luminosity, with a large dispersion. We find that star-forming galaxies at these redshifts are distributed along the main sequence in the stellar mass vs. SFR plane, described with a slope {alpha}=0.85+/-0.05. We report a flat evolution of the specific SFR compared to lower redshift measurements. We find that the UV luminosity function is best reproduced by a double power law, while a fit with a Schechter function is only marginally inferior. The Ly{alpha} luminosity function is best fitted with a Schechter function. We derive a logSFRD_UV_(M_{sun}_/yr/Mpc^3^)=-1.45^+0.06^_-0.08_ and logSFRD_Ly{alpha}_(M_{sun}_/yr/Mpc^3^)=-1.40^+0.07^_-0.08_. The SFRD derived from the Ly{alpha} luminosity function is in excellent agreement with the UV-derived SFRD after correcting for IGM absorption.Conclusions. Our new SFRD measurements at a mean redshift of z=5.6 are ~0.2dex above the mean SFRD reported in Madau & Dickinson (2014ARA&A..52..415M), but in excellent agreement with results from Bouwens et al. (2015ApJ...803...34B). These measurements confirm the steep decline of the SFRD at z>2. The bright end of the Ly{alpha} luminosity function has a high number density, indicating a significant star formation activity concentrated in the brightest LAE at these redshifts. LAE with equivalent width EW>25{AA} contribute to about 75% of the total UV-derived SFRD. While our analysis favors low dust content in 5.0<z<6.6, uncertainties on the dust extinction correction and associated degeneracy in spectral fitting will remain an issue, when estimating the total SFRD until future surveys extending spectroscopy to the NIR rest-frame spectral domain, such as with JWST.
- ID:
- ivo://CDS.VizieR/J/ApJS/150/1
- Title:
- VV29 and NGC 4676 HST photometry
- Short Name:
- J/ApJS/150/1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the analysis of the faint galaxy population in the Advanced Camera for Surveys (ACS) Early Release Observation fields VV 29 (UGC 10214) and NGC 4676. These observations cover a total area of 26.3arcmin^2^ and have depths close to that of the Hubble Deep Fields in the deepest part of the VV 29 image, with 10{sigma} detection limits for point sources of 27.8, 27.6, and 27.2 AB magnitudes in the g_F475W_, V_F606W_, and I_F814W_ bands, respectively.
4079. VVDS14h redshift catalog
- ID:
- ivo://CDS.VizieR/J/MNRAS/473/1879
- Title:
- VVDS14h redshift catalog
- Short Name:
- J/MNRAS/473/1879
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use observations made with the Giant Metrewave Radio Telescope (GMRT) to probe the neutral hydrogen (HI) gas content of field galaxies in the VIMOS VLT Deep Survey (VVDS) 14h field at z~=0.32. Because the HI emission from individual galaxies is too faint to detect at this redshift, we use an HI spectral stacking technique using the known optical positions and redshifts of the 165 galaxies in our sample to co-add their HI spectra and thus obtain the average HI mass of the galaxies. Stacked HI measurements of 165 galaxies show that >~95 per cent of the neutral gas is found in blue, star-forming galaxies. Among these galaxies, those having lower stellar mass are more gas rich than more massive ones. We apply a volume correction to our HI measurement to evaluate the HI gas density at z~=0.32 as {OMETA}_HI_=(0.50+/-0.18)x10^-3^ in units of the cosmic critical density. This value is in good agreement with previous results at z<0.4, suggesting no evolution in the neutral hydrogen gas density over the last ~4Gyr. However the z~=0.32 gas density is lower than that at z~5 by at least a factor of two.
- ID:
- ivo://CDS.VizieR/J/A+A/646/A146
- Title:
- VVV galaxies behind Galactic bulge overdensity
- Short Name:
- J/A+A/646/A146
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The extragalactic vision we have through the Milky Way is very unclear. There is significant extinction of the optical emission from objects located in the region called the Zone of Avoidance (ZOA). NIR wavelengths are less affected by extinction, and therefore the infrared surveys in this zone are a potential source of astronomical discoveries. Nevertheless, these observations need to be compared with cosmological simulations in order to carry out high-accuracy studies. Our aim is to identify extragalactic sources in the ZOA, using infrared images of the VVV survey. We consider mock galaxy catalogues in order to interpret observational results. We studied a region of 1.636 square degrees corresponding to the VVV tile b204. Using SExtractor, we analysed photometric data generating a catalogue of extended sources in this area. In order to confirm these sources as galaxy candidates we visually inspected RGB images looking for typical galaxy features. Using 2MASX and GCMW catalogued sources we tested completeness and contamination of our catalogue and define suitable colour cuts to select galaxies. We also compared the observational results with those obtained from two semi-analytical models on Dark Matter simulations. One galaxy catalogue was constructed with the SAG semi-analytic model of galaxy formation, and the other one was constructed with the L-Galaxies semi-analytic model. By adopting CLASS_STAR<0.5, r1/2>0.7 arcsec and specific colour cuts (J-Ks>0.97, J-H>0 and H-Ks>0) we generated an automatic catalogue of extended sources. After visual inspection we identified 624 sources with 10<Ks<17 as galaxy candidates.The contamination of the automatic catalogue is 28% when considering visually confirmed galaxies as reliable objects. The estimated completeness is 87% up to magnitude Ks=13.5. We analysed the spatial distribution of galaxy candidates, finding a high concentration of galaxies in a small region of 15 arcmin radius. This region has three times higher density than similar areas in the tile. We compared the number of galaxies in this small area with the mean density values obtained from a suitable sample of galaxies from semi-analytic models finding that our results are consistent with an overdensity region. Using VVV near-infrared data and mock catalogues we detect new extragalactic sources that have not been identified by other catalogues. We demonstrate the potentiality of the VVV survey in finding and studying a large number of galaxy candidates and extragalactic structures obscured by the Milky Way.
