- ID:
- ivo://CDS.VizieR/J/A+A/485/475
- Title:
- AMIGA. VI. Radio fluxes of the isolated galaxies
- Short Name:
- J/A+A/485/475
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper is part of a series that describes the results of the AMIGA (Analysis of the interstellar Medium of Isolated GAlaxies) project, studying the largest sample of very isolated galaxies in the local Universe. The study of the radio properties of the AMIGA sample is intended to characterize the radio continuum emission for a sample least affected by the local environment, thus providing a reference against which less isolated and interacting samples can be compared. Radio continuum data at 325, 1420, and 4850MHz were extracted from the WENSS, NVSS/FIRST, and GB6 surveys, respectively. The source extractions have been obtained from reprocessing the data and new detections added to the cross- matched detections with the respective survey catalogs. We focus on the complete AMIGA subsample composed of 719 galaxies. A catalog of radio fluxes was obtained from the above four surveys. Comparison between the NVSS and FIRST detections indicates that the radio continuum is coming from disk-dominated emission in spiral galaxies, in contrast to the results found in high-density environments where nuclear activity is more frequent. The comparison of the radio continuum power with a comparable sample, which is however not selected with respect to its environment, the Condon et al. UGC-SF sample of star-forming field galaxies, shows a lower mean value for the AMIGA sample. We have obtained radio-to-optical flux ratios (R) using the NVSS radio continuum flux. The distribution of R for the AMIGA galaxies is consistent with a sample dominated by radio emission from star formation (SF) and a small number of active galactic nuclei (AGN), with less than 3% of the sample with R>100. We derived the radio luminosity function (RLF) and total power density of the radio continuum emission for the AMIGA sample at 1.4GHz, and compared them with results from other low-redshift studies. The Schechter fit of the RLF indicates a major weight of the low-luminosity galaxies. The results indicate the very low level of radio continuum emission in our sample of isolated galaxies, which is dominated by mild disk SF. It confirms thus the AMIGA sample as a suitable template to effectively quantify the role of interactions in samples extracted from denser environments.
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- ID:
- ivo://CDS.VizieR/J/A+A/472/121
- Title:
- AMIGA V. Isolation parameters
- Short Name:
- J/A+A/472/121
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The AMIGA project aims to build a well defined and statistically significant reference sample of isolated galaxies in order to estimate the environmental effects on the formation and evolution of galaxies. The goal of this paper is to provide a measure of the environment of the isolated galaxies in the AMIGA sample, quantifying the influence of the candidate neighbours identified in our previous work and their potential effects on the evolution of the primary galaxies. Here we provide a quantification of the isolation degree of the galaxies in this sample.
- ID:
- ivo://CDS.VizieR/J/A+A/609/A17
- Title:
- AMIGA XIII. HI properties
- Short Name:
- J/A+A/609/A17
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the largest catalogue of HI single dish observations of isolated galaxies to date, as part of the multi-wavelength compilation being performed by the AMIGA project (Analysis of the interstellar Medium in Isolated GAlaxies). Despite numerous studies of the HI content of galaxies, no revision has been made for the most isolated L* galaxies since Haynes & Giovanelli (1984AJ.....89..758H). The AMIGA sample has been demonstrated to be almost "nurture free", therefore, by creating scaling relations for the HI content of these galaxies we will define a metric of HI normalcy in the absence of interactions. The catalogue comprises of our own HI observations with Arecibo, Effelsberg, Nancay and GBT, and spectra collected from the literature. In total we have measurements or constraints on the HI masses of 844 galaxies from the Catalogue of Isolated Galaxies (CIG). The multi-wavelength AMIGA dataset includes a revision of the B-band luminosities, optical diameters, morphologies, and isolation. Due to the large size of the catalogue, these revisions permit cuts to be made to ensure isolation and a high level of completeness, which was not previously possible. With this refined dataset we fit HI scaling relations based on luminosity, optical diameter and morphology. Our regression model incorporates all the data, including upper limits, and accounts for uncertainties in both variables, as well as distance uncertainties. The HI scaling relations of the AMIGA sample define an up-to-date metric of the HI content of almost "nurture free" galaxies. These relations allow the expected HI mass, in the absence of interactions, of an individual galaxy to be predicted to within 0.25dex (for typical measurement uncertainties). These relations are thus suitable for use as statistical measures of the impact of interactions on the neutral gas content of galaxies.
- ID:
- ivo://CDS.VizieR/J/A+A/545/A15
- Title:
- AMIGA XI. Optical nuclear activity
- Short Name:
- J/A+A/545/A15
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This study was performe within the frame of the AMIGA project (http://amiga.iaa.es/). We obtained spectral data from the 6th Data Release of the Sloan Digital Sky Survey, which were inspected in a semi-automatic way. We subtracted the underlying stellar populations from the spectra (using the software Starlight) and modelled the nuclear emission features. Standard emission-line diagnostics diagrams were applied, using a new classification scheme that takes into account censored data, to classify the type of nuclear emission. We provide a final catalogue of spectroscopic data, stellar populations, emission lines and classification of optical nuclear activity for AMIGA galaxies. The prevalence of optical active galactic nuclei (AGN) in AMIGA galaxies is 20.4%, or 36.7% including transition objects. The fraction of AGN increases steeply towards earlier morphological types and higher luminosities. We compare these results with a matched analysis of galaxies in isolated denser environments (Hickson Compact Groups). After correcting for the effects of the morphology and luminosity, we find that there is no evidence for a difference in the prevalence of AGN between isolated and compact group galaxies, and we discuss the implications of this result. We find that a major interaction is not a necessary condition for the triggering of optical AGN.
- ID:
- ivo://CDS.VizieR/J/A+A/540/A47
- Title:
- AMIGA X. Isolated galaxy colors
- Short Name:
- J/A+A/540/A47
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The basic properties of galaxies can be affected by both nature (internal processes) or nurture (interactions and effects of environment). Deconvolving the two effects is an important current effort in astrophysics. Observed properties of a sample of isolated galaxies should be mainly the result of internal (natural) evolution. It follows that nurture-induced galaxy evolution can only be understood through a comparative study of galaxies in different environments. We take a first look at SDSS (g-r) colors of galaxies in the AMIGA sample, which consists of many of the most isolated galaxies in the local Universe. This alerted us at the same time the pitfalls of using automated SDSS colors.
- ID:
- ivo://CDS.VizieR/J/ApJ/714/25
- Title:
- AMUSE-Virgo survey. II.
- Short Name:
- J/ApJ/714/25
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We complete the census of nuclear X-ray activity in 100 early-type Virgo galaxies observed by the Chandra X-ray Telescope as part of the AMUSE-Virgo survey, down to a (3{sigma}) limiting luminosity of 3.7x10^38^erg/s over 0.5-7keV. The stellar mass distribution of the targeted sample, which is mostly composed of formally "inactive" galaxies, peaks below 10^10^M_{sun}_, a regime where the very existence of nuclear supermassive black holes (SMBHs) is debated. Out of 100 objects, 32 show a nuclear X-ray source, including 6 hybrid nuclei which also host a massive nuclear cluster as visible from archival Hubble Space Telescope images. After carefully accounting for contamination from nuclear low-mass X-ray binaries based on the shape and normalization of their X-ray luminosity function (XLF), we conclude that between 24% and 34% of the galaxies in our sample host an X-ray active SMBH (at the 95% confidence level). This sets a firm lower limit to the black hole (BH) occupation fraction in nearby bulges within a cluster environment.
- ID:
- ivo://CDS.VizieR/J/AJ/159/167
- Title:
- AMUSING++ nearby galaxy compilation. I. Sample
- Short Name:
- J/AJ/159/167
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present here the All-weather MUse Supernova Integral-field of Nearby Galaxies (AMUSING++): the largest compilation of nearby galaxies observed with the Multi Unit Spectroscopic Explorer (MUSE) integral-field spectrograph so far. This collection consists of 635 galaxies from different MUSE projects covering the redshift interval 0.0002<z<0.1. The sample and its main properties are characterized and described here. It includes galaxies of almost all morphological types, with a good coverage in its color-magnitude diagram, within the stellar mass range between 10^8^ and 10^12^M{sun}, and with properties resembling those of a diameter-selected sample. The AMUSING++ sample is, therefore, suitable for studying, with unprecedented detail, the properties of nearby galaxies at global and local scales, providing us with more than 50 million individual spectra. We use this compilation to investigate the presence of galactic outflows. We exploit the use of combined emission-line images to explore the shape of the different ionized components and the distribution along classical diagnostic diagrams to disentangle the different ionizing sources across the optical extension of each galaxy. We use the cross-correlation function to estimate the level of symmetry of the emission lines as an indication of the presence of shocks and/or active galactic nuclei. We uncovered a total of 54 outflows, comprising ~8% of the sample. A large number of the discovered outflows correspond to those driven by active galactic nuclei (~60%), suggesting some bias in the selection of our sample. No clear evidence was found that outflow host galaxies are highly star-forming, and outflows appear to be found within all galaxies around the star-formation sequence.
- ID:
- ivo://CDS.VizieR/J/ApJ/788/125
- Title:
- An ALMA survey of ECDFS submillimeter galaxies
- Short Name:
- J/ApJ/788/125
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first photometric redshift distribution for a large sample of 870 {mu}m submillimeter galaxies (SMGs) with robust identifications based on observations with ALMA. In our analysis we consider 96 SMGs in the Extended Chandra Deep Field South, 77 of which have 4-19 band photometry. We model the SEDs for these 77 SMGs, deriving a median photometric redshift of z_phot_=2.3+/-0.1. The remaining 19 SMGs have insufficient photometry to derive photometric redshifts, but a stacking analysis of Herschel observations confirms they are not spurious. Assuming that these SMGs have an absolute H-band magnitude distribution comparable to that of a complete sample of z~1-2 SMGs, we demonstrate that they lie at slightly higher redshifts, raising the median redshift for SMGs to z_phot_=2.5+/-0.2. Critically we show that the proportion of galaxies undergoing an SMG-like phase at z>=3 is at most 35%+/-5% of the total population. We derive a median stellar mass of M_*_=(8+/-1)x10^10^ M_{sun}_, although there are systematic uncertainties of up to 5x for individual sources. Assuming that the star formation activity in SMGs has a timescale of ~100 Myr, we show that their descendants at z~0 would have a space density and M_H_ distribution that are in good agreement with those of local ellipticals. In addition, the inferred mass-weighted ages of the local ellipticals broadly agree with the look-back times of the SMG events. Taken together, these results are consistent with a simple model that identifies SMGs as events that form most of the stars seen in the majority of luminous elliptical galaxies at the present day.
- ID:
- ivo://CDS.VizieR/J/ApJS/212/18
- Title:
- An atlas of UV-to-MIR galaxy SEDs
- Short Name:
- J/ApJS/212/18
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an atlas of 129 spectral energy distributions for nearby galaxies, with wavelength coverage spanning from the ultraviolet to the mid-infrared. Our atlas spans a broad range of galaxy types, including ellipticals, spirals, merging galaxies, blue compact dwarfs, and luminous infrared galaxies. We have combined ground-based optical drift-scan spectrophotometry with infrared spectroscopy from Spitzer and Akari with gaps in spectral coverage being filled using Multi-wavelength Analysis of Galaxy Physical Properties spectral energy distribution models. The spectroscopy and models were normalized, constrained, and verified with matched-aperture photometry measured from Swift, Galaxy Evolution Explorer, Sloan Digital Sky Survey, Two Micron All Sky Survey, Spitzer, and Wide-field Infrared Space Explorer images. The availability of 26 photometric bands allowed us to identify and mitigate systematic errors present in the data. Comparison of our spectral energy distributions with other template libraries and the observed colors of galaxies indicates that we have smaller systematic errors than existing atlases, while spanning a broader range of galaxy types. Relative to the prior literature, our atlas will provide improved K-corrections, photometric redshifts, and star-formation rate calibrations.
- ID:
- ivo://CDS.VizieR/J/A+A/385/39
- Title:
- 13 and 22cm radio flux from A3571
- Short Name:
- J/A+A/385/39
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this paper we report and discuss the results of a radio survey in the A3571 cluster complex, a structure located in the Shapley Concentration core, and formed by the three clusters A3571, A3572 and A3575. The survey was carried out simultaneously at 22cm and 13cm with the Australia Telescope Compact Array, and led to the detection of 124 radio sources at 22cm. The radio source counts in this region are in agreement with the background counts. Among the 36 radio sources with optical counterpart, six have a measured redshift that places them at the distance of the A3571 cluster complex, and nine radio sources have optical counterparts most likely members of this cluster complex. All of the radio galaxies emit at low power level, i.e. P_22cm_<=10^22.6^ W/Hz. A number of them are likely to be starburst galaxies.
