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301. CENSORS infrared imaging
ID:
ivo://CDS.VizieR/J/MNRAS/366/1265
Title:
CENSORS infrared imaging
Short Name:
J/MNRAS/366/1265
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Combined EIS-NVSS Survey of Radio Sources (CENSORS) is a 1.4-GHz radio survey selected from the National Radio Astronomy Observatories (NRAO) Very Large Array (VLA) Sky Survey (NVSS) and complete to a flux density of 7.2mJy. It targets the European Southern Observatory (ESO) Imaging Survey (EIS) Patch D, which is a 3x2{deg}^2^ field centred on right ascension 09:51:36.0 and declination 21:00:00 (J2000). This paper presents K-band imaging of 142 of the 150 CENSORS sources. The primary motivation for beginning infrared imaging of the sample was to identify the host galaxies of ~30 per cent of sources for which the EIS I-band imaging failed to produce a likely candidate. In addition, K-band magnitudes allow photometric redshift estimation and IK colours aid the identification of host galaxies (which are typically old, red ellipticals). Of the sources observed in the I and K bands, four remain undetected, possibly indicating high redshifts for the host galaxies, and eight involve complicated radio structures, or several candidate host galaxies, which have yet to be resolved. Thus, the host galaxy identifications are brought to 92 per cent completeness.
302. CENSORS + other 1.4GHz sources
ID:
ivo://CDS.VizieR/J/MNRAS/416/1900
Title:
CENSORS + other 1.4GHz sources
Short Name:
J/MNRAS/416/1900
Date:
21 Oct 2021
Publisher:
CDS
Description:
This paper presents a new grid-based method for investigating the evolution of the steep-spectrum radio luminosity function, with the aim of quantifying the high-redshift cut-off suggested by previous work. To achieve this, the Combined EIS-NVSS Survey of Radio Sources (CENSORS) has been developed; this is a 1.4-GHz radio survey, containing 135 sources complete to a flux density of 7.2mJy, selected from the NRAO VLA Sky Survey (NVSS) over 6deg^2^ of the ESO Imaging Survey Patch D (EISD). The sample is currently 7% spectroscopically complete, with the remaining redshifts estimated via the K-z or I-z magnitude-redshift relation. CENSORS is combined with additional radio data from the Parkes All-Sky, Parkes Selected Regions, Hercules and Very Large Array (VLA) COSMOS samples to provide comprehensive coverage of the radio power versus redshift plane. The redshift distributions of these samples, together with radio source count determinations, and measurements of the local luminosity function, provide the input to the fitting process.
303. CENSORS spectroscopic observations
ID:
ivo://CDS.VizieR/J/MNRAS/385/1297
Title:
CENSORS spectroscopic observations
Short Name:
J/MNRAS/385/1297
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Combined EIS-NVSS Survey Of Radio Sources (CENSORS) is a 1.4-GHz radio survey selected from the NRAO VLA Sky Survey (NVSS) and complete to a flux density of 7.2mJy. It targets the ESO Imaging Survey (EIS) Patch D, which is a 3x2deg^2^ field centred on 09:51:36.0-21:00:00 (J2000). This paper presents the results of spectroscopic observations of 143 of the 150 CENSORS sources. The primary motivation for these observations is to achieve sufficient spectroscopic completeness so that the sample may be used to investigate the evolution of radio sources. The observations result in secure spectroscopic redshifts for 63 per cent of the sample and likely redshifts (based on a single emission line, for example) for a further 8 per cent. Following the identification of the quasars and star-forming galaxies in the CENSORS sample, estimated redshifts are calculated for the remainder of the sample via the K-z relation for radio galaxies.
304. Census of the Local Universe survey. I. CLU-Halpha
ID:
ivo://CDS.VizieR/J/ApJ/880/7
Title:
Census of the Local Universe survey. I. CLU-Halpha
Short Name:
J/ApJ/880/7
Date:
03 Nov 2021 07:51:08
Publisher:
CDS
Description:
We present the Census of the Local Universe (CLU) narrowband survey to search for emission-line (H{alpha}) galaxies. CLU-H{alpha} has imaged ~3{pi} of the sky (26470deg^2^) with four narrowband filters that probe a distance out to 200Mpc. We have obtained spectroscopic follow-up for galaxy candidates in 14 preliminary fields (101.6deg^2^) to characterize the limits and completeness of the survey. In these preliminary fields, CLU can identify emission lines down to an H{alpha} flux limit of 10^-14^erg/s/cm^2^ at 90% completeness, and recovers 83% (67%) of the H{alpha} flux from cataloged galaxies in our search volume at the {Sigma}=2.5 ({Sigma}=5) color excess levels. The contamination from galaxies with no emission lines is 61% (12%) for {Sigma}=2.5 ({Sigma}=5). Also, in the regions of overlap between our preliminary fields and previous emission-line surveys, we recover the majority of the galaxies found in previous surveys and identify an additional ~300 galaxies. In total, we find 90 galaxies with no previous distance information, several of which are interesting objects: 7 blue compact dwarfs, 1 green pea, and a Seyfert galaxy; we also identify a known planetary nebula. These objects show that the CLU-H{alpha} survey can be a discovery machine for objects in our own Galaxy and extreme galaxies out to intermediate redshifts. However, the majority of the CLU-H{alpha} galaxies identified in this work show properties consistent with normal star-forming galaxies. CLU-H{alpha} galaxies with new redshifts will be added to existing galaxy catalogs to focus the search for the electromagnetic counterpart to gravitational wave events.
305. Cepheids from VVV in the southern Galactic midplane
ID:
ivo://CDS.VizieR/J/ApJ/883/58
Title:
Cepheids from VVV in the southern Galactic midplane
Short Name:
J/ApJ/883/58
Date:
21 Oct 2021
Publisher:
CDS
Description:
The far side of the Milky Way's disk is one of the most concealed parts of the known universe due to extremely high interstellar extinction and point-source density toward low Galactic latitudes. Large time-domain photometric surveys operating in the near-infrared hold great potential for the exploration of these vast uncharted areas of our Galaxy. We conducted a census of distant classical and type II Cepheids along the southern Galactic midplane using near-infrared photometry from the VISTA Variables in the Via Lactea survey. We performed a machine-learned classification of the Cepheids based on their infrared light curves using a convolutional neural network. We have discovered 640 distant classical Cepheids with up to ~40mag of visual extinction and over 500 type II Cepheids, most of them located in the inner bulge. Intrinsic color indices of individual Cepheids were predicted from sparse photometric data using a neural network, allowing their use as accurate reddening tracers. They revealed a steep, spatially varying near-infrared extinction curve toward the inner bulge. Type II Cepheids in the Galactic bulge were also employed to measure robust mean selective-to-absolute extinction ratios. They trace a centrally concentrated spatial distribution of the old bulge population with a slight elongation, consistent with earlier results from RR Lyrae stars. Likewise, the classical Cepheids were utilized to trace the Galactic warp and various substructures of the Galactic disk and uncover significant vertical and radial age gradients of the thin disk population at the far side of the Milky Way.
306. Cepheids in M31 - PAndromeda Cepheid sample
ID:
ivo://CDS.VizieR/J/AJ/156/130
Title:
Cepheids in M31 - PAndromeda Cepheid sample
Short Name:
J/AJ/156/130
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the largest Cepheid sample in M31 based on the complete Pan-STARRS1 survey of Andromeda (PAndromeda) in the r_P1_, i_P1_, and g_P1_ bands. We find 2686 Cepheids with 1662 fundamental-mode Cepheids, 307 first-overtone Cepheids, 278 type II Cepheids, and 439 Cepheids with undetermined Cepheid type. Using the method developed by Kodric et al. (2013, , Cat. J/AJ/145/106), we identify Cepheids by using a three-dimensional parameter space of Fourier parameters of the Cepheid light curves combined with a color cut and other selection criteria. This is an unbiased approach to identify Cepheids and results in a homogeneous Cepheid sample. The period-luminosity relations obtained for our sample have smaller dispersions than in our previous work. We find a broken slope that we previously observed with HST data in Kodric et al. (2013, , Cat. J/AJ/145/106), albeit with a lower significance.
307. 4C equatorial sample VLA observations. II.
ID:
ivo://CDS.VizieR/J/A+AS/134/401
Title:
4C equatorial sample VLA observations. II.
Short Name:
J/A+AS/134/401
Date:
21 Oct 2021
Publisher:
CDS
Description:
VLA observations at 4.9GHz are given for 144 steep-spectrum 4C sources whose declinations are between -4{deg} and +4{deg} and whose angular sizes are smaller than 30arcsec. The paper contains 150 maps (VLA and 6 MERLIN observations at 1420 or 1658MHz) which are not included here.
308. CfA, CSP, BSP and LOSS spec. & phot. of SNe Ia
ID:
ivo://CDS.VizieR/J/ApJ/882/120
Title:
CfA, CSP, BSP and LOSS spec. & phot. of SNe Ia
Short Name:
J/ApJ/882/120
Date:
21 Oct 2021
Publisher:
CDS
Description:
SNe Ia play key roles in revealing the accelerating expansion of the universe, but our knowledge of their progenitors is still very limited. Here we report the discovery of a rigid dichotomy in circumstellar (CS) environments around two subclasses of SNe Ia as defined by their distinct photospheric velocities. For the SNe Ia with high photospheric velocities (HVs), we found a significant excess flux in blue light 60-100 days past maximum, while this phenomenon is absent for SNe with normal photospheric velocity. This blue excess can be attributed to light echoes by circumstellar dust located at a distance of about (1-2)x10^17^cm from the HV subclass. Moreover, we also found that the HV SNe Ia show systematically evolving NaI absorption line by performing a systematic search of variable NaI absorption lines in spectra of all SNe Ia, whereas this evolution is rarely seen in normal ones. The evolving NaI absorption can be modeled in terms of photoionization model, with the location of the gas clouds at a distance of about 2x10^17^cm, in striking agreement with the location of CS dust inferred from B-band light-curve excess. These observations show clearly that the progenitors of HV subclass are likely from single-degenerate progenitor system (i.e., symbiotic binary), while the NV subclass may arise from double-degenerate system.
309. CFH Blue Grens Quasar Candidates
ID:
ivo://CDS.VizieR/J/AJ/104/1706
Title:
CFH Blue Grens Quasar Candidates
Short Name:
J/AJ/104/1706
Date:
21 Oct 2021
Publisher:
CDS
Description:
(no description available)
310. CF-HiZELS survey
ID:
ivo://CDS.VizieR/J/MNRAS/451/2303
Title:
CF-HiZELS survey
Short Name:
J/MNRAS/451/2303
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present results from the largest contiguous narrow-band survey in the near-infrared. We have used the wide-field infrared camera/Canada-France-Hawaii Telescope and the lowOH2 filter (1.187+/-0.005{mu}m) to survey ~10deg^2^ of contiguous extragalactic sky in the SA22 field. A total of ~6000 candidate emission-line galaxies are found. We use deep ugrizJK data to obtain robust photometric redshifts. We combine our data with the High-redshift(Z) Emission Line Survey (HiZELS), explore spectroscopic surveys (VVDS, VIPERS) and obtain our own spectroscopic follow-up with KMOS, FMOS and MOSFIRE to derive large samples of high-redshift emission-line selected galaxies: 3471 H{alpha} emitters at z=0.8, 1343 [OIII] + H{beta} emitters at z=1.4 and 572 [OII] emitters at z=2.2. We probe comoving volumes of >10^6^Mpc^3^ and find significant overdensities, including an 8.5{sigma} (spectroscopically confirmed) overdensity of H{alpha} emitters at z=0.81. We derive H{alpha}, [OIII] + H{beta} and [OII] luminosity functions at z=0.8, 1.4, 2.2, respectively, and present implications for future surveys such as Euclid. Our uniquely large volumes/areas allow us to subdivide the samples in thousands of randomized combinations of areas and provide a robust empirical measurement of sample/cosmic variance. We show that surveys for star-forming/emission-line galaxies at a depth similar to ours can only overcome cosmic-variance (errors <10 percent) if they are based on volumes >5x10^5^Mpc^3^; errors on L* and {phi}* due to sample (cosmic) variance on surveys probing ~10^4^ and ~10^5^Mpc^3^ are typically very high: ~300 and ~40-60 percent, respectively.

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