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641. 21cm observations of 452 galaxies
ID:
ivo://CDS.VizieR/J/A+A/465/71
Title:
21cm observations of 452 galaxies
Short Name:
J/A+A/465/71
Date:
21 Oct 2021
Publisher:
CDS
Description:
This paper presents 452 new 21-cm neutral hydrogen line measurements carried out with the FORT receiver of the meridian transit Nancay radiotelescope (NRT) in the period April 2003-March 2005. This observational programme is part of a larger project aiming at collecting an exhaustive and magnitude-complete HI extragalactic catalogue for Tully-Fisher applications (the so-called KLUN project, for Kinematics of the Local Universe studies, end in 2008). The whole on-line HI archive of the NRT contains today reduced HI-profiles for ~4500 spiral galaxies of declination delta >-40{deg} (http://klun.obs-nancay.fr). As an example of application, we use direct Tully-Fisher relation in three (JHK) bands in deriving distances to a large catalog of 3126 spiral galaxies distributed through the whole sky and sampling well the radial velocity range between 0 and 8000km/s. Thanks to an iterative method accounting for selection bias and smoothing effects, we show as a preliminary output a detailed and original map of the velocity field in the Local Universe.
642. 20cm survey of the AKARI NEP
ID:
ivo://CDS.VizieR/J/A+A/517/A54
Title:
20cm survey of the AKARI NEP
Short Name:
J/A+A/517/A54
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Westerbork Radio Synthesis Telescope, WSRT, has been used to make a deep radio survey of an ~1.7degree^2^ field coinciding with the AKARI north ecliptic pole deep field. The observations, data reduction and source count analysis are presented, along with a description of the overall scientific objectives. The survey consisted of 10 pointings, mosaiced with enough overlap to maintain a similar sensitivity across the central region that reached as low as 21uJy/beam at 1.4GHz.
643. CNOC cluster redshift survey catalogs. II.
ID:
ivo://CDS.VizieR/J/ApJS/102/289
Title:
CNOC cluster redshift survey catalogs. II.
Short Name:
J/ApJS/102/289
Date:
21 Oct 2021
Publisher:
CDS
Description:
A photometric and redshift catalog of galaxies in the field of the rich galaxy cluster Abell 2390 (z=0.228) is presented as part of the Canadian Network for Observation Cosmology (CNOC) cluster redshift survey carried out at the Canada-France-Hawaii Telescope (CFHT) using the MOS imaging multiobject spectrograph. Using five separate fields, the imaging and spectroscopic observations cover a strip of approximately 7.3'x43.2', centered on the cluster. Redshifts for 327 galaxies, primarily ranging in magnitude from r=17 to 22, were obtained. The data set is also presented graphically in several forms. The magnitude, geometric, and color selection functions for the redshift sample are discussed and presented.
644. CNOC cluster redshift survey catalogs. III.
ID:
ivo://CDS.VizieR/J/ApJS/113/1
Title:
CNOC cluster redshift survey catalogs. III.
Short Name:
J/ApJS/113/1
Date:
21 Oct 2021
Publisher:
CDS
Description:
A photometric and redshift catalog of galaxies in the field of two rich galaxy clusters, MS 1621.5+2640 (z=0.4275) and MS 0302.7+1658 (z=0.4245), is presented as part of the Canadian Network for Observation Cosmology (CNOC) Cluster Redshift Survey carried out at the Canada-France-Hawaii Telescope (CFHT) using the MOS imaging multiobject spectrograph. The imaging and spectroscopic observations cover strips cantered on each cluster of approximately 23.3'x9.0', and 7.9'x9.0', for MS 1621.5+2640 and MS 0302.7+1658, respectively. Redshifts for 371 galaxies, primarily ranging in magnitude from r=20 to 22, were obtained. The data set is also presented graphically in several forms. The magnitude, color, and geometric selection functions for the redshift sample are presented and discussed.
645. CNOC cluster redshift survey catalogs. IV.
ID:
ivo://CDS.VizieR/J/ApJS/116/211
Title:
CNOC cluster redshift survey catalogs. IV.
Short Name:
J/ApJS/116/211
Date:
21 Oct 2021
Publisher:
CDS
Description:
Photometric and redshift catalogs of galaxies in the field of two rich galaxy clusters, MS 1358.4+6245 (z=0.328) and MS 1008.1-1224 (z=0.306), are presented as part of the Canadian Network for Observation Cosmology (CNOC) cluster redshift survey carried out at the Canada-France-Hawaii Telescope (CFHT) using the MOS imaging multiobject spectrograph. The imaging and spectroscopic observations cover a mosaic of three MOS fields in the north-south direction of a total area of approximately 23.3'x9.0' for MS 1358.4+6245 and a single field of 7.9'x9.0' for MS 1008.1-1224. Redshifts for 361 galaxies, primarily ranging in magnitude from r=20 to r=22, and Gunn r and g photometry for 3015 galaxies to r=24mag were obtained. The data set is also presented graphically in several forms. The magnitude, color, and geometric selection functions for the redshift sample are presented and discussed.
646. CNOC cluster redshift survey catalogs. V.
ID:
ivo://CDS.VizieR/J/ApJS/116/231
Title:
CNOC cluster redshift survey catalogs. V.
Short Name:
J/ApJS/116/231
Date:
21 Oct 2021
Publisher:
CDS
Description:
Photometric and redshift catalogs of galaxies in the field of two rich galaxy clusters: MS 1224.7+2007 (z=0.327) and MS 1512.4+3647 (z=0.372) are presented as part of the Canadian Network for Observation Cosmology (CNOC) cluster redshift survey carried out at the Canada-France-Hawaii Telescope (CFHT) using the MOS imaging multiobject spectrograph. The imaging and spectroscopic observations span three contiguous MOS fields in the east-west direction for MS 1512.4+3647, covering a total area of approximately 8.0'x27.3'. A single field of 7.1'x9.0' was obtained for MS 1224.7+2007. Redshifts for 287 galaxies in the MS 1512.4+3647 fields and 75 galaxies in the MS 1224.7+2007 field (primarily ranging in magnitude from r=18-22) were obtained. The spectroscopic information in this paper is supplemented by photometric information for all galaxies in the fields down to Gunn r=21mag. The data set is also presented graphically in several forms. The magnitude, color, and geometric selection functions for the redshift sample are presented and discussed.
647. CNOC cluster redshift survey catalogs. VI.
ID:
ivo://CDS.VizieR/J/ApJS/116/247
Title:
CNOC cluster redshift survey catalogs. VI.
Short Name:
J/ApJS/116/247
Date:
21 Oct 2021
Publisher:
CDS
Description:
A photometric and redshift catalog of galaxies in the field of two rich galaxy clusters, MS 0015.9+1609 (z=0.5481) and MS 0451.5-0305 (z=0.5386), is presented as part of the Canadian Network for Observation Cosmology (CNOC) cluster redshift survey carried out at the Canada-France-Hawaii Telescope (CFHT) using the MOS imaging multiobject spectrograph. The imaging and spectroscopic observations cover a single field of approximately 7.6'x9.1', centered on each cluster. Redshifts for 247 galaxies, primarily ranging in magnitude from r=20 to r=22, were obtained. The data set is also presented graphically in several forms. The magnitude, color, and geometric selection functions for the redshift sample are presented and discussed.
648. CNSS pilot survey
ID:
ivo://CDS.VizieR/J/ApJ/818/105
Title:
CNSS pilot survey
Short Name:
J/ApJ/818/105
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have commenced a multiyear program, the Caltech-NRAO Stripe 82 Survey (CNSS), to search for radio transients with the Jansky VLA in the Sloan Digital Sky Survey Stripe 82 region. The CNSS will deliver five epochs over the entire ~270deg^2^ of Stripe 82, an eventual deep combined map with an rms noise of ~40{mu}Jy and catalogs at a frequency of 3 GHz, and having a spatial resolution of 3". This first paper presents the results from an initial pilot survey of a 50deg^2^ region of Stripe 82, involving four epochs spanning logarithmic timescales between 1 week and 1.5yr, with the combined map having a median rms noise of 35{mu}Jy. This pilot survey enabled the development of the hardware and software for rapid data processing, as well as transient detection and follow-up, necessary for the full 270deg^2^ survey. Data editing, calibration, imaging, source extraction, cataloging, and transient identification were completed in a semi-automated fashion within 6 hr of completion of each epoch of observations, using dedicated computational hardware at the NRAO in Socorro and custom-developed data reduction and transient detection pipelines. Classification of variable and transient sources relied heavily on the wealth of multiwavelength legacy survey data in the Stripe 82 region, supplemented by repeated mapping of the region by the Palomar Transient Factory. A total of 3.9_-0.9_^+0.5^% of the few thousand detected point sources were found to vary by greater than 30%, consistent with similar studies at 1.4 and 5 GHz. Multiwavelength photometric data and light curves suggest that the variability is mostly due to shock-induced flaring in the jets of active galactic nuclei (AGNs). Although this was only a pilot survey, we detected two bona fide transients, associated with an RS CVn binary and a dKe star. Comparison with existing legacy survey data (FIRST, VLA-Stripe 82) revealed additional highly variable and transient sources on timescales between 5 and 20yr, largely associated with renewed AGN activity. The rates of such AGNs possibly imply episodes of enhanced accretion and jet activity occurring once every ~40,000yr in these galaxies. We compile the revised radio transient rates and make recommendations for future transient surveys and joint radio-optical experiments.
649. Coadded rotation curves of disk galaxies
ID:
ivo://CDS.VizieR/J/A+A/643/A161
Title:
Coadded rotation curves of disk galaxies
Short Name:
J/A+A/643/A161
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Lambda-cold dark matter (Lambda CDM) scenario is able to describe the Universe at large scales, but clearly shows some serious difficulties at small scales. The core/cusp issue is one of those: as a fact, the inner dark matter (DM) density profiles of spiral galaxies generally appear to be cored, without the r^-1^ profile as predicted by N-body simulations in the above scenario. It is well known that, in a more physical context, the baryons in the galaxy, through supernovae explosions could back react and erase the original cusp. Before investigating the efficiency and the presence of such effect, it is important to know how wide and how frequent the discrepancy between observed and N-body predicted profiles is and what its features are. We use more than 3200 good quality and high resolution, quite extended rotation curves (RCs) of disk systems including normal and dwarf spirals as well as low surface brightness galaxies covering their whole ranges of magnitudes. All these RCs are condensed in 26 coadded RCs, each of them built with individual RCs of galaxies of similar luminosity and morphology. We mass model these 26 RCs using the NFW profile for the contribution of the DM halo to the circular velocity and the exponential Freeman disk for that of the stellar disk. The fits are generally poor in all the 26 cases: in several cases we find chi^2^_red_> 2. Moreover, the best fitting values of three parameters of the model (c, M_D_, M_{vir}_) combined with those of their 1-sigma uncertainty show clear conflict with well-known expectations of Lambda-CDM scenario. We also test the scaling relations which exist in spirals with the outcome of the current mass modelling: the latter is found not to account for such scaling relations. The results of testing NFW profile in disk systems indicate that such DM halo density law cannot account for the kinematics of the whole family of disk galaxies. The need of transforming initial cusps in the observed cores is therefore mandatory for the success of the Lambda-CDM scenario, in any disk galaxy of any luminosity or maximum rotational velocity.
650. CO and CaT derived sigma in spiral galaxies
ID:
ivo://CDS.VizieR/J/MNRAS/446/2823
Title:
CO and CaT derived sigma in spiral galaxies
Short Name:
J/MNRAS/446/2823
Date:
21 Oct 2021
Publisher:
CDS
Description:
We examine the stellar velocity dispersions ({sigma}) of a sample of 48 galaxies, 35 of which are spirals, from the Palomar nearby galaxy survey. It is known that for ultra-luminous infrared galaxies (ULIRGs) and merger remnants, the {sigma} derived from the near-infrared CO band heads is smaller than that measured from optical lines, while no discrepancy between these measurements is found for early-type galaxies. No such studies are available for spiral galaxies - the subject of this paper. We used cross-dispersed spectroscopic data obtained with the Gemini Near-Infrared Spectrograph, with spectral coverage from 0.85 to 2.5{mu}m, to obtain {sigma} measurements from the 2.29{mu}m CO band heads ({sigma}CO) and the 0.85{mu}m calcium triplet ({sigma}_CaT_). For the spiral galaxies in the sample, we found that {sigma}_CO_ is smaller than {sigma}_CaT_, with a mean fractional difference of 14.3 per cent. The best fit to the data is given by {sigma}_opt_=(46.0+/-18.1)+(0.85+/-0.12){sigma}_CO_. This '{sigma}-discrepancy' may be related to the presence of warm dust, as suggested by a slight correlation between the discrepancy and the infrared luminosity. This is consistent with studies that have found no {sigma}-discrepancy in dust-poor early-type galaxies, and a much larger discrepancy in dusty merger remnants and ULIRGs. That {sigma}_CO_ is lower than {sigma}opt may also indicate the presence of a dynamically cold stellar population component. This would agree with the spatial correspondence between low-{sigma}_CO_ and young/intermediate-age stellar populations that has been observed in spatially resolved spectroscopy of a handful of galaxies.