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531. 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.
532. Census of self-obscured massive stars
ID:
ivo://CDS.VizieR/J/ApJ/715/1094
Title:
Census of self-obscured massive stars
Short Name:
J/ApJ/715/1094
Date:
21 Oct 2021
Publisher:
CDS
Description:
A new link in the causal mapping between massive stars and potentially fatal explosive transients opened with the 2008 discovery of the dust-obscured progenitors of the luminous outbursts in NGC 6946 and NGC 300. Here, we carry out a systematic mid-IR photometric search for massive, luminous, and self-obscured stars in four nearby galaxies: M33, NGC 300, M81, and NGC 6946. For detection, we use only the 3.6um and 4.5um IRAC bands, as these can still be used for multi-epoch Spitzer surveys of nearby galaxies (<~10Mpc). We combine familiar point-spread function and aperture photometry with an innovative application of image subtraction to catalog the self-obscured massive stars in these galaxies. In particular, we verify that stars analogous to the progenitors of the NGC 6946 (SN 2008S) and NGC 300 transients are truly rare in all four galaxies: their number may be as low as ~1 per galaxy at any given moment. This result empirically supports the idea that the dust-enshrouded phase is a very short lived phenomenon in the lives of many massive stars and that these objects constitute a natural extension of the asymptotic giant branch sequence. We also provide mid-IR catalogs of sources in NGC 300, M81, and NGC 6946.
533. 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.
534. Centaurus A (NGC 5128) 185MHz MWA image
ID:
ivo://CDS.VizieR/J/other/NatAs/6.109
Title:
Centaurus A (NGC 5128) 185MHz MWA image
Short Name:
J/other/NatAs/6.
Date:
22 Feb 2022
Publisher:
CDS
Description:
Supermassive black holes and supernovae explosions at the centres of active galaxies power cycles of outflowing and inflowing gas that affect galactic evolution and the overall structure of theUniverse. While simulations and observations show that this must be the case, the range of physical scales (over ten orders of magnitude) and paucity of available tracers, make both the simulation and observation of these effects difficult. By serendipity, there lies an active galaxy, Centaurus A (NGC 5128), at such a close proximity as to allow its observation over this entire range of scales and across the entire electromagnetic spectrum. In the radio band, however, details on scales of 10-100kpc from the supermassive black hole have so far been obscured by instrumental limitations. Here we report low-frequency radio observations that overcome these limitations and show evidence for a broad, bipolar outflow with velocity 1100 km per s and mass outflow rate of 2.9 solar masses per year on these scales. We combine our data with the plethora of multi-scale, multi-wavelength historical observations of Centaurus A to probe a unified view of feeding and feedback, which we show to be consistent with the Chaotic Cold Accretion self-regulation scenario.
535. Centaurus Cluster catalog
ID:
ivo://CDS.VizieR/J/ApJS/170/95
Title:
Centaurus Cluster catalog
Short Name:
J/ApJS/170/95
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a catalog of all galaxies with V<=22.0 and R_iso_>3" within a 0.83deg^2^ region centered on the Centaurus Cluster (Abell 3526) at RA=12h48m, DE=-41{deg}18'. V-band total magnitudes along with other photometric parameters were obtained from the detection programs FOCAS and SExtractor and also from fitting curve-of-growth Sersic functions to the galaxy profiles. Central surface brightnesses, half-light radii, ellipticity, and position angles are presented, along with (B-V) aperture colors where B-band data were obtained. This work is part of a larger program to study the cluster-to-cluster variation in the faint end of the LF based on the study of eight clusters, including Centaurus. We discuss our data reduction methods in this paper. More detailed analyses and science results will be presented in subsequent papers.
536. Centers of early-type galaxies with HST
ID:
ivo://CDS.VizieR/J/AJ/129/2138
Title:
Centers of early-type galaxies with HST
Short Name:
J/AJ/129/2138
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present observations of 77 early-type galaxies imaged with the PC1 CCD of the Hubble Space Telescope (HST) WFPC2. "Nuker-law" parametric fits to the surface brightness profiles are used to classify the central structure into "core" or "power-law" forms.
537. 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.
538. Central surface brightness of 30000 SDSS galaxies
ID:
ivo://CDS.VizieR/J/ApJ/722/L120
Title:
Central surface brightness of 30000 SDSS galaxies
Short Name:
J/ApJ/722/L120
Date:
21 Oct 2021
Publisher:
CDS
Description:
Disc central surface brightness for 30000 galaxies from the Sloan Digitized Sky Survey (SDSS) Data Release 7, in the r-band. Virtual Observatory methods and tools were used to define, retrieve and analyze the images for this unprecedentedly large sample classified as spiral galaxies in the LEDA catalogue. These parameters are also available for all other SDSS bands (u,g,i,z), and they can be retrieved from the Author.
539. Central surface densities in SPARC disk galaxies
ID:
ivo://CDS.VizieR/J/ApJ/827/L19
Title:
Central surface densities in SPARC disk galaxies
Short Name:
J/ApJ/827/L19
Date:
21 Oct 2021
Publisher:
CDS
Description:
We use the Spitzer Photometry and Accurate Rotation Curves (SPARC) database to study the relation between the central surface density of stars {Sigma}_*_(0) and dynamical mass {Sigma}_dyn_(0) in 135 disk galaxies (S0 to dIrr). We find that {Sigma}_dyn_(0) correlates tightly with {Sigma}_*_(0) over 4dex. This central density relation can be described by a double power law. High surface brightness galaxies are consistent with a 1:1 relation, suggesting that they are self-gravitating and baryon dominated in the inner parts. Low surface brightness (LSB) galaxies systematically deviate from the 1:1 line, indicating that the dark matter contribution progressively increases but remains tightly coupled to the stellar one. The observed scatter is small (~0.2dex) and largely driven by observational uncertainties. The residuals show no correlations with other galaxy properties like stellar mass, size, or gas fraction.
540. 90 cepheid candidates nearby NGC 6814
ID:
ivo://CDS.VizieR/J/ApJ/885/161
Title:
90 cepheid candidates nearby NGC 6814
Short Name:
J/ApJ/885/161
Date:
08 Mar 2022
Publisher:
CDS
Description:
We present a Cepheid-based distance to the nearby Seyfert galaxy NGC6814 from Hubble Space Telescope observations. We obtained F555W and F814W imaging over the course of 12 visits with logarithmic time spacing in 2013 August-October. We detected and made photometric measurements for 16469 unique sources across all images in both filters, from which we identify 90 excellent Cepheid candidates spanning a range of periods of 13-84days. We find evidence for incompleteness in the detection of candidates at periods <21days. Based on the analysis of Cepheid candidates above the incompleteness limit, we determine a distance modulus for NGC6814 relative to the LMC of {mu}_rel,LMC_=13.200_-0.031_^+0.031^mag. Adopting the recent constraint of the distance modulus to the LMC determined by Pietrzynski et al., we find m-M=31.677_-0.041_^+0.041^ which gives a distance of 21.65{+/-}0.41Mpc to NGC6814.