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981. Emission-line strengths for 129 galaxies
ID:
ivo://CDS.VizieR/J/MNRAS/469/1186
Title:
Emission-line strengths for 129 galaxies
Short Name:
J/MNRAS/469/1186
Date:
21 Oct 2021
Publisher:
CDS
Description:
We propose a method to substantially increase the flexibility and power of template fitting-based photometric redshifts by transforming a large number of galaxy spectral templates into a corresponding collection of 'fuzzy archetypes' using a suitable set of perturbative priors designed to account for empirical variation in dust attenuation and emission-line strengths. To bypass widely separated degeneracies in parameter space (e.g. the redshift-reddening degeneracy), we train self-organizing maps (SOMs) on large 'model catalogues' generated from Monte Carlo sampling of our fuzzy archetypes to cluster the predicted observables in a topologically smooth fashion. Subsequent sampling over the SOM then allows full reconstruction of the relevant probability distribution functions (PDFs). This combined approach enables the multimodal exploration of known variation among galaxy spectral energy distributions with minimal modelling assumptions. We demonstrate the power of this approach to recover full redshift PDFs using discrete Markov chain Monte Carlo sampling methods combined with SOMs constructed from Large Synoptic Survey Telescope ugrizY and Euclid YJH mock photometry.
982. EMPIRE: IRAM 30m dense gas survey
ID:
ivo://CDS.VizieR/J/ApJ/880/127
Title:
EMPIRE: IRAM 30m dense gas survey
Short Name:
J/ApJ/880/127
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present EMPIRE, an IRAM 30m large program that mapped {lambda}=3-4mm dense gas tracers at ~1-2kpc resolution across the whole star-forming disk of nine nearby massive spiral galaxies. We describe the EMPIRE observing and reduction strategies and show new whole-galaxy maps of HCN(1-0), HCO^+^(1-0), HNC(1-0), and CO(1-0). We explore how the HCN-to-CO and IR-to-HCN ratios, observational proxies for the dense gas fraction and dense gas star formation efficiency, depend on host galaxy and local environment. We find that the fraction of dense gas correlates with stellar surface density, gas surface density, molecular-to-atomic gas ratio, and dynamical equilibrium pressure. In EMPIRE, the star formation rate per unit dense gas is anticorrelated with these same environmental parameters. Thus, although dense gas appears abundant in the central regions of many spiral galaxies, this gas appears relatively inefficient at forming stars. These results qualitatively agree with previous work on nearby galaxies and the Milky Way's Central Molecular Zone. To first order, EMPIRE demonstrates that the conditions in a galaxy disk set the gas density distribution and that the dense gas traced by HCN shows an environment-dependent relation to star formation. However, our results also show significant (+/-0.2dex) galaxy-to-galaxy variations. We suggest that gas structure below the scale of our observations and dynamical effects likely also play an important role.
983. End of red sequence galaxies in Galaxy Zoo
ID:
ivo://CDS.VizieR/J/MNRAS/420/1684
Title:
End of red sequence galaxies in Galaxy Zoo
Short Name:
J/MNRAS/420/1684
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a study of local post-starburst galaxies (PSGs) using the photometric and spectroscopic observations from the Sloan Digital Sky Survey and the results from the Galaxy Zoo project. We find that the majority of our local PSG population have neither early- nor late-type morphologies but occupy a well-defined space within the colour-stellar mass diagram, most notably, the low-mass end of the 'green valley' below the transition mass thought to be the mass division between low-mass star-forming galaxies and high-mass passively evolving bulge-dominated galaxies.
984. Energy distributions of radio galaxies
ID:
ivo://CDS.VizieR/J/AJ/105/853
Title:
Energy distributions of radio galaxies
Short Name:
J/AJ/105/853
Date:
21 Oct 2021
Publisher:
CDS
Description:
Far-infrared observations of 140 radio galaxies from the 3CR and B2 catalogs are presented. The galaxies span a range of over four order of magnitude in the radio power, from weak nuclear sources in nearby galaxies, to powerful FR II doubled-lobed sources at moderate redshift. Scanned or pointed observations with IRAS detect 38 of the radio galaxies in at least one waveband; 21 are detected at both 60 and 100 {mu}m. The strength of the far-infrared emission is more closely correlated with core radio emission than with total radio emission, and it is independent of the absolute visual magnitude of the host galaxy. The more luminous 3CR galaxies have warmer far infrared emission than the less luminous B2 galaxies. The relationship between radio and far-infrared luminosity is determined in a way that is insensitive to the large number of infrared nondetections. Radio galaxies have far-infrared emission with similar color temperatures to normal ellipticals; however the inferred amounts of cold interstellar material are typical of gas-rich galaxies. Infrared luminous radio galaxies are rare. Only one in 10^5^ ellipticals with M_V_<-17 has a strong enough radio core to have 10^11^ L_Sun_ of far-infrared emission. Indirect arguments indicates that far-infrared emission in radio galaxies represents star formation that is more closely tied to the active nucleus than to the global properties of the galaxy. The far-infrared luminosity function shows good continuity between radio galaxies and radio loud quasars.
985. Environmental COntext (ECO) catalog
ID:
ivo://CDS.VizieR/J/ApJ/812/89
Title:
Environmental COntext (ECO) catalog
Short Name:
J/ApJ/812/89
Date:
21 Oct 2021
Publisher:
CDS
Description:
We study the relationships between galaxy environments and galaxy properties related to disk (re)growth, considering two highly complete samples that are approximately baryonic mass limited into the high-mass dwarf galaxy regime, the Environmental COntext (ECO) catalog (data release herein) and the B-semester region of the REsolved Spectroscopy Of a Local VolumE (RESOLVE) survey. We quantify galaxy environments using both group identification and smoothed galaxy density field methods. We use by-eye and quantitative morphological classifications plus atomic gas content measurements and estimates. We find that blue early-type (E/S0) galaxies, gas-dominated galaxies, and UV-bright disk host galaxies all become distinctly more common below group halo mass ~10^11.5^M_{sun}_, implying that this low group halo mass regime may be a preferred regime for significant disk growth activity. We also find that blue early-type and blue late-type galaxies inhabit environments of similar group halo mass at fixed baryonic mass, consistent with a scenario in which blue early-types can regrow late-type disks. In fact, we find that the only significant difference in the typical group halo mass inhabited by different galaxy classes is for satellite galaxies with different colors, where at fixed baryonic mass red early- and late-types have higher typical group halo masses than blue early- and late-types. More generally, we argue that the traditional morphology-environment relation (i.e., that denser environments tend to have more early-types) can be largely attributed to the morphology-galaxy mass relation for centrals and the color-environment relation for satellites.
986. Environment of galaxies in the 5 CANDELS fields
ID:
ivo://CDS.VizieR/J/ApJ/890/7
Title:
Environment of galaxies in the 5 CANDELS fields
Short Name:
J/ApJ/890/7
Date:
17 Jan 2022 00:15:58
Publisher:
CDS
Description:
We present a robust method, weighted von Mises kernel density estimation, along with boundary correction to reconstruct the underlying number density field of galaxies. We apply this method to galaxies brighter than Hubble Space Telescope/F160w<=26 AB mag in the redshift range 0.4<=z<=5 in the five CANDELS fields (GOODS-N, GOODS-S, EGS, UDS, and COSMOS). We then use these measurements to explore the environmental dependence of the star formation activity of galaxies. We find strong evidence of environmental quenching for massive galaxies (M>~10^11^M_{sun}_) out to z~3.5 such that an overdense environment hosts >~20% more massive quiescent galaxies than an underdense region. We also find that environmental quenching efficiency grows with stellar mass and reaches ~60% for massive galaxies at z~0.5. The environmental quenching is also more efficient than stellar mass quenching for low-mass galaxies (M>~10^10^M_{sun}_) at low and intermediate redshifts (z<~1.2). Our findings concur thoroughly with the "overconsumption" quenching model where the termination of cool gas accretion (cosmological starvation) happens in an overdense environment and the galaxy starts to consume its remaining gas reservoir in depletion time. The depletion time depends on the stellar mass and could explain the evolution of environmental quenching efficiency with stellar mass.
987. Environments of moderate redshift radio galaxies
ID:
ivo://CDS.VizieR/J/AJ/135/1311
Title:
Environments of moderate redshift radio galaxies
Short Name:
J/AJ/135/1311
Date:
21 Oct 2021
Publisher:
CDS
Description:
In the local universe, high-power radio galaxies live in lower-density environments than low-luminosity radio galaxies. If this trend continued to higher redshifts, powerful radio galaxies would serve as efficient probes of moderate redshift groups and poor clusters. Photometric studies of radio galaxies at 0.3<~z<~0.5 suggest that the radio luminosity-environment correlation disappears at moderate redshifts, though this could be the result of foreground/background contamination affecting the photometric measures of environment. We have obtained multi-object spectroscopy in the fields of 14 lower luminosity (L_1.4GHz_<4x10^24^W/Hz) and higher luminosity (L_1.4GHz_>1.2x10^25^W/Hz) radio galaxies at z~0.3 to spectroscopically investigate the link between the environment and the radio luminosity of radio galaxies at moderate redshifts. Our results support the photometric analyses; there does not appear to be a correlation between the luminosity of a radio galaxy and its environment at moderate redshifts. Hence, radio galaxies are not efficient signposts for group environments at moderate redshifts.
988. Equivalent widths of 9 RGB in Carina dSph
ID:
ivo://CDS.VizieR/J/ApJ/751/102
Title:
Equivalent widths of 9 RGB in Carina dSph
Short Name:
J/ApJ/751/102
Date:
21 Oct 2021
Publisher:
CDS
Description:
The detailed abundances of 23 chemical elements in nine bright red giant branch stars in the Carina dwarf spheroidal galaxy are presented based on high-resolution spectra gathered at the Very Large Telescope (VLT) and Magellan telescopes. A spherical model atmospheres analysis is applied using standard methods (local thermodynamic equilibrium and plane-parallel radiative transfer) to spectra ranging from 380 to 680nm. Stellar parameters are found to be consistent between photometric and spectroscopic analyses, both at moderate and high resolution. The stars in this analysis range in metallicity from -2.9<[Fe/H]<-1.3, and adopting the ages determined by Lemasle et al. (Cat. J/A+A/538/A100), we are able to examine the chemical evolution of Carina's old and intermediate-aged populations.
989. Equivalent widths of VMF73 and VMF74 galaxies
ID:
ivo://CDS.VizieR/J/A+A/421/59
Title:
Equivalent widths of VMF73 and VMF74 galaxies
Short Name:
J/A+A/421/59
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a spectroscopic analysis of two galaxy clusters out to ~4Mpc at z~0.2. The two clusters VMF73 and VMF74 identified by Vikhlinin et al. (1998, Cat. <J/ApJ/502/558>) were observed with MOSCA at the Calar Alto 3.5m telescope. Both clusters lie in the ROSAT PSPC field R285 and were selected from the X-ray Dark Cluster Survey (Gilbank et al., 2004MNRAS.348..551G) that provides optical V- and I-band data. VMF73 and VMF74 are located at respective redshifts of z=0.25 and z=0.18 with velocity dispersions of 671km/s and 442km/s, respectively. The spectroscopic observations reach out to ~2.5 virial radii. Line strength measurements of the emission lines H_alpha and [OII]3727 are used to assess the star formation activity of cluster galaxies which show radial and density dependences. The mean and median of both line strength distributions as well as the fraction of star forming galaxies increase with increasing clustercentric distance and decreasing local galaxy density. Except for two galaxies with strong H_alpha and [OII] emission, all of the cluster galaxies are normal star forming or passive galaxies. Our results are consistent with other studies that show the truncation in star formation occurs far from the cluster centre.
990. EROs in Groth Strip
ID:
ivo://CDS.VizieR/J/MNRAS/414/2246
Title:
EROs in Groth Strip
Short Name:
J/MNRAS/414/2246
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a new catalogue of EROs from the Groth Strip and study the relation between their morphology and mass. With a selection criterion F814W-Ks>=4 and Ks<=21.0 we find 102 EROs, over a survey area of 155 arcmin2, leading to a surface density of 0.66arcmin^-2^. The photometric data include U, B, F606W, F814W, J, Ks bands. Morphologies are based on a by eye classification and we distinguish between three basic classes: compact objects, targets with a disc and/or a bulge component and irregular or merger candidates. An additional group consists of the few objects which could not be classified.

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