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341. 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.
342. Center-to-limb variation of quiet Sun
ID:
ivo://CDS.VizieR/J/A+A/423/1109
Title:
Center-to-limb variation of quiet Sun
Short Name:
J/A+A/423/1109
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present new observations of the center-to-limb variation of spectral lines in the quiet Sun. Our long-slit spectra are corrected for scattered light, which amounts to 4-8% of the continuum intensity, by comparison with a Fourier transform spectrum of the disk center. Different spectral lines exhibit different behaviors, depending on their sensitivity to the physical conditions in the photosphere and the range of depths they probe as a function of the observing angle, providing a rich database to test models of the solar photosphere and line formation.
343. Central black holes of spiral galaxies
ID:
ivo://CDS.VizieR/J/AJ/131/1236
Title:
Central black holes of spiral galaxies
Short Name:
J/AJ/131/1236
Date:
21 Oct 2021
Publisher:
CDS
Description:
Central black hole masses for 117 spiral galaxies representing morphological stages S0/a through Sc and taken from the large spectroscopic survey of Ho et al. (Cat. <J/ApJS/112/315>) are derived using Ks-band data from the Two Micron All Sky Survey. Black hole masses are found using a calibrated black hole-Ks bulge luminosity relation, while bulge luminosities are measured by means of a two-dimensional bulge-disk decomposition routine.
344. Central stars of planetary nebulae. II.
ID:
ivo://CDS.VizieR/J/A+A/531/A172
Title:
Central stars of planetary nebulae. II.
Short Name:
J/A+A/531/A172
Date:
21 Oct 2021
Publisher:
CDS
Description:
There are more than 3000 confirmed and probably known Galactic planetary nebulae (PNe), but central star spectroscopic information is available for only 13% of them. We have undertaken a spectroscopic survey of the central stars in PNe to identify their spectral types. We performed spectroscopic observations at low resolution with the 2-m telescope at CASLEO, Argentina. We present the spectra of 46 central stars of PNe, most of them are OB-type and emission-line stars.
345. Cetus dSph stellar chemo-kinematics
ID:
ivo://CDS.VizieR/J/A+A/618/A122
Title:
Cetus dSph stellar chemo-kinematics
Short Name:
J/A+A/618/A122
Date:
21 Oct 2021
Publisher:
CDS
Description:
Cetus is an isolated, dwarf spheroidal (dSph) galaxy at a distance of 755kpc. In order to quantify its stellar chemo-kinematical properties, we observed individual red giants branch stars in Cetus with the Very Large Telescope (VLT) FORS2 instrument, in Mask eXchange Unit (MXU) configuration. The kinematic analysis shows that Cetus is a mainly pressure-supported ({sigma}_v_=11.0^+1.6^_-1.3_km/s), dark-matter-dominated system (M_1/2_/L_V_=23.9^+9.7^_-8.9_M_{sun}_/L_{sun}_) with no significant signs of internal rotation. We find Cetus to be a metal-poor system with a significant metallicity spread (median [Fe/H]=-1.71dex, median-absolute-deviation =0.49dex), as expected for its stellar mass. We report the presence of a mild metallicity gradient compatible with those found in other dSphs of the same luminosity; we trace the presence of a stellar population gradient also in the spatial distribution of stars in different evolutionary phases in ancillary photometric data. There are tentative indications of two chemo-kinematically distinct sub-populations, with the more metal-poor stars showing a hotter kinematics than the metal-richer ones. Our results add Cetus to the growing scatter in stellar-dark matter halo properties in low-mass galactic systems. The presence of a metallicity gradient akin to those found in similar systems inhabiting different environments may hint at metallicity gradients in Local Group early-type dwarfs being driven by internal mechanisms.
346. 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.
347. CFRS II: 0000-00 and 1000+25 fields
ID:
ivo://CDS.VizieR/J/ApJ/455/60
Title:
CFRS II: 0000-00 and 1000+25 fields
Short Name:
J/ApJ/455/60
Date:
21 Oct 2021
Publisher:
CDS
Description:
This paper describes the methods used to obtain the spectroscopic data and construct redshift catalogs for the Canada-France Deep Redshift Survey (CFRS). The full data set consists of more than 1000 spectra, of objects with 17.5=<I_AB_=<22.5, obtained from deep multislit data with the MARLIN and MOS-SIS spectrographs at the Canada-France-Hawaii Telescope (CFHT). The final spectroscopic catalog contains 200 stars, 591 galaxies with secure redshifts in the range 0=<z=<1.3, six QSOs, and 146 objects with very uncertain or unknown redshifts, leading to an overall success rate of identification of 85%. In addition, 67 objects affected by observational problems have been placed in a supplemental list. We describe here the instrumental setup and the observing procedures used to gather this large data set efficiently. New optimal ways of packing spectra on the detector to increase significantly the multiplexing gain offered by multislit spectroscopy are described. Dedicated data reduction procedures have been developed under the IRAF environment to allow for fast and accurate processing. Very strict procedures have been followed to establish a reliable list of final spectroscopic measurements. Fully independent processing of the data has been carried out by three members of the team for each data set associated with a multislit mask, and final redshifts were assigned only after the careful comparison of the three independent measurements. A confidence class scheme was established. We strongly emphasize the benefits of such procedures. Finally, we present the spectroscopic data obtained for 303 objects in the 0000-00 and 1000+25 fields. The success rate in spectroscopic identification is 83% for the 0000-00 field and 84% for the 1000+25 field.
348. CFRS III: 1415+52 and 2215+00 fields
ID:
ivo://CDS.VizieR/J/ApJ/455/75
Title:
CFRS III: 1415+52 and 2215+00 fields
Short Name:
J/ApJ/455/75
Date:
21 Oct 2021
Publisher:
CDS
Description:
This paper is one of a series describing the Canada-France Redshift Survey (CFRS). It is shown how the shape of the continuum around the emission line can be used to distinguish between [O II]{lambda}3727 at z>0.76 and H{alpha} at low redshift in spectra for which only a single isolated emission line is visible. Based on this, [O II]{lambda}3727 is most likely to be the emission line in most of the single emission-line galaxies in the CFRS. The statistics of the repeated observations are analyzed to derive an empirical calibration of the reliability of the spectroscopic identifications in the CFRS in order to determine how often additional observations could lead to the identification of an initially unidentified object and to provide an estimate of the internal velocity accuracy. Finally, the results of spectroscopic observations of 413 objects in the 1415+52 and 2215+00 CFRS survey fields are presented.
349. CFRS IV: 0300+00 field
ID:
ivo://CDS.VizieR/J/ApJ/455/88
Title:
CFRS IV: 0300+00 field
Short Name:
J/ApJ/455/88
Date:
21 Oct 2021
Publisher:
CDS
Description:
Possible surface brightness selection effects in the redshift catalogs of the Canada-France Redshift Survey are investigated through comparisons of subsamples of the data. Our analyses demonstrate that the securing of redshifts is independent of possible biases arising from surface brightness effects and/or differing galaxy morphologies and orientations. The unusual geometry of the mask designs for our spectroscopic observations also do not produce any significant bias. There is, however, a bias at the highest and lowest redshifts, especially for absorption-line galaxies at z>1 and z<0.2, due to the adopted spectral range (4250-8500A). Apart from the latter, we conclude that our sample of identified galaxies is an unbiased subsample of the original photometric catalog and is essentially limited by I-band flux density (17.5<I_AB_<22.5). Finally, spectroscopic data for the remaining CFRS field is presented. Data for 272 objects in the 0300+0000 field are given.
350. CFRS XIV. Field galaxies up to z=1
ID:
ivo://CDS.VizieR/J/ApJ/481/49
Title:
CFRS XIV. Field galaxies up to z=1
Short Name:
J/ApJ/481/49
Date:
21 Oct 2021
Publisher:
CDS
Description:
The spectral properties of more than 400 Canada-France Redshift Survey (CFRS) galaxies and their changes over the redshift interval 0<=z<=1.3 are investigated. Emission-line intensities and equivalent widths for accessible lines have been measured, as well as continuum color indices based on 200{AA} wide spectral regions.

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