- ID:
- ivo://CDS.VizieR/J/A+A/463/455
- Title:
- Nearby early-type gal. with ionized gas. III.
- Short Name:
- J/A+A/463/455
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The paper is devoted to the study of the underlying stellar population of a sample of 62 nearby early-type galaxies, predominantly located in low density environments, a large fraction of which showing emission lines. Ages, metallicities and [{alpha}/Fe] ratios have been derived through the comparison of Lick indices measured at different galacto-centric distances (7 apertures and 4 gradients) with new Simple Stellar Population (SSP) models which account for the presence of alpha/Fe-enhancement. The SSPs cover a wide range of ages (10^8^-16x10^9^yr), metallicities (0.0004<=Z<=0.05) and [{alpha}/Fe] ratios (0-0.8). To derive the stellar population parameters we use an algorithm that provides, together with the most likely solution in the (age, Z, [{alpha}/Fe]) space, also the probability density function along the age-metallicity degeneracy. We derive a large spread in age, with SSP-equivalent ages ranging from a few to 15Gyrs. Age does not show any significant trend with central velocity dispersion sigma_c_ but E galaxies appear on average older than lenticulars.
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2412. Nearby Galaxies
- ID:
- ivo://CDS.VizieR/VII/161
- Title:
- Nearby Galaxies
- Short Name:
- VII/161
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The sample contains the galaxies with a velocity less than 500km/s with respect to the centroid of the Local Group. The inclusion of a galaxy into the catalog depends on its redshift as in the catalogue of Kraan-Korteweg and Tammann (1979) or on the fact that the objects are known to be certain or probable member of nearby groups. The galaxies in this catalogue form the Local Group, but one third of the galaxies does not seem to belong to any group. For a detailed explanation of the astrophysical meaning of the columns, please refer in any case to the explanation given in Schmidt and Boller (1992). Concerning the references, the basic list of references is given in Schmidt & Boller (1992). The dust masses of six dwarf irregular galaxies (LGS3, U3974, A0818+71, U8091, D210, U12613) are taken from Young et al. (1989). Additional data for several galaxies, especially on the apparent magnitudes as well as on the profile width of the 21 cm line at the level 50 per cent of the maximum value, are taken from a recent preprint by Karachentsev (1993).
- ID:
- ivo://CDS.VizieR/J/MNRAS/471/1743
- Title:
- Nearby galaxies abundances
- Short Name:
- J/MNRAS/471/1743
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We combine samples of nearby galaxies with Herschel photometry selected on their dust, metal, HI and stellar mass content, and compare these to chemical evolution models in order to discriminate between different dust sources. In a companion paper, we used an HI-selected sample of nearby galaxies to reveal a subsample of very gas-rich (gas fraction >80 per cent) sources with dust masses significantly below predictions from simple chemical evolution models, and well below M_d_/M_*_ and M_d_/M_gas_ scaling relations seen in dust and stellar-selected samples of local galaxies. We use a chemical evolution model to explain these dust-poor, but gas-rich, sources as well as the observed star formation rates (SFRs) and dust-to-gas ratios. We find that (i) a delayed star formation history is required to model the observed SFRs; (ii) inflows and outflows are required to model the observed metallicities at low gas fractions; (iii) a reduced contribution of dust from supernovae (SNe) is needed to explain the dust-poor sources with high gas fractions. These dust-poor, low stellar mass galaxies require a typical core-collapse SN to produce 0.01-0.16M_{sun}_ of dust. To match the observed dust masses at lower gas fractions, significant grain growth is required to counteract the reduced contribution from dust in SNe and dust destruction from SN shocks. These findings are statistically robust, though due to intrinsic scatter it is not always possible to find one single model that successfully describes all the data. We also show that the dust-to-metal ratio decreases towards lower metallicity.
- ID:
- ivo://CDS.VizieR/VII/145
- Title:
- Nearby Galaxies Catalogue (NBG)
- Short Name:
- VII/145
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- (no description available)
- ID:
- ivo://CDS.VizieR/J/AJ/127/3273
- Title:
- Nearby galaxies HI observations
- Short Name:
- J/AJ/127/3273
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A survey of 329 nearby galaxies (redshift z<0.045) has been conducted to study the distribution of mass and light within spiral galaxies over a range of environments. The 18 observed clusters and groups span a range of richness, density, and X-ray temperature and are supplemented by a set of 30 isolated field galaxies. Optical spectroscopy taken with the 200inch (5m) Hale Telescope provides separately resolved H{alpha} and [NII] major-axis rotation curves for the complete set of galaxies, which are analyzed to yield velocity widths and profile shapes, extents, and gradients. HI line profiles provide an independent velocity width measurement and a measure of HI gas mass and distribution. I-band images are used to deconvolve profiles into disk and bulge components, to determine global luminosities and ellipticities, and to check morphological classification. These data are combined to form a unified data set ideal for the study of the effects of environment upon galaxy evolution.
- ID:
- ivo://CDS.VizieR/J/A+A/609/A37
- Title:
- 875 nearby galaxies multiwavelength photometry
- Short Name:
- J/A+A/609/A37
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The DustPedia project is capitalising on the legacy of the Herschel Space Observatory, using cutting-edge modelling techniques to study dust in the 875 DustPedia galaxies - representing the vast majority of extended galaxies within 3000km/s that were observed by Herschel. This work requires a database of multiwavelength imagery and photometry that greatly exceeds the scope (in terms of wavelength coverage and number of galaxies) of any previous local-Universe survey. We constructed a database containing our own custom Herschel reductions, along with standardised archival observations from GALEX, SDSS, DSS, 2MASS, WISE, Spitzer, and Planck. Using these data, we performed consistent aperture-matched photometry, which we combined with external supplementary photometry from IRAS and Planck. We present our multiwavelength photometry across 40 UV-microwave bands for the 875 DustPedia galaxies. Our aperture-matched photometry, combined with the external supplementary photometry, represents a total of 21,857 photometric measurements. A typical DustPedia galaxy has multiwavelength photometry spanning 25 bands. To carry out our photometry we developed the Comprehensive & Adaptable Aperture Photometry Routine (CAAPR). CAAPR is designed to produce consistent photometry for the enormous range of galaxy and observation types in our data. In particular, CAAPR is able to determine robust cross-compatible uncertainties, thanks to a novel method for reliably extrapolating the aperture noise for observations that cover a very limited amount of background.
- ID:
- ivo://CDS.VizieR/J/A+A/428/877
- Title:
- 4 nearby galaxies velocities & line-strengths
- Short Name:
- J/A+A/428/877
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present observations of four nearby early-type galaxies previously known (Rest et al., 2001AJ....121.2431R) to have nuclear stellar disks using two instruments on-board the Hubble Space Telescope. We observed NGC 4128, NGC 4612, and NGC 5308 with the Wide Field Planetary Camera 2, and the same three galaxies, plus NGC 4570, with the Space Telescope Imaging Spectrograph. We have detected a red nucleus in NGC 4128, a blue nucleus in NGC 4621, and a blue disk in NGC 5308. Additionally, we have discovered a blue disk-like feature with position angle ~15{deg} from the major axis in NGC 4621. In NGC 5308 there is evidence for a blue region along the minor axis. We discovered a blue transient on the images of NGC 4128 at position 0.14" west and 0.32" north from the nucleus. The extracted kinematic profiles belong to two groups: fast (NGC 4570 and NGC 5308) and kinematically disturbed rotators (NGC 4128 and NGC 4621). We report the discovery of a kinematically decoupled core in NGC 4128. Galaxies have mostly old (10-14Gyr) stellar populations with large spread in metallicities (sub- to super-solar). We discuss the possible formation scenarios, including bar-driven secular evolution and the influence of mergers, which can explain the observed color and kinematic features.
- ID:
- ivo://CDS.VizieR/J/MNRAS/471/4990
- Title:
- Nearby galaxy clusters X-ray point sources
- Short Name:
- J/MNRAS/471/4990
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this work, we studied 10 nearby (z<=0.038) galaxy clusters to understand possible interactions between hot plasma and member galaxies. A multi-band source detection was applied to detect point-like structures within the intra-cluster medium. We examined the spectral properties of a total of 391 X-ray point sources within each cluster's potential well. log N versus log S was studied in the energy range 2-10 keV to measure X-ray overdensities. Optical overdensities were also calculated to solve suppression/triggering phenomena for nearby galaxy clusters. X-ray and optical flux/luminosity properties (X/O, L_X_/L_B_ and L_X_/L_K_) were investigated for optically identified member galaxies. The X-ray luminosities of our point sources were found to be faint [40.08<=log(L_X_)<=42.39erg/s]. The luminosity range of point sources reveals possible contributions to X-ray emission from low-luminosity active galactic nuclei, X-ray binaries and star formation. We estimated ~2 times higher X-ray overdensities from galaxies within galaxy clusters compared to fields. Our results demonstrate that optical overdensities are much higher than X-ray overdensities at a cluster's centre, whereas X-ray overdensities increase through the outskirts of clusters. We conclude that high pressure from a cluster's centre affects the balance of galaxies and they lose a significant amount of their fuel. As a result, the clustering process quenches the X-ray emission of the member galaxies. We also find evidence that the existence of X-ray bright sources within a cluster environment can be explained by two main phenomena: contributions from off-nuclear sources and/or active galactic nucleus (AGN) triggering caused by galaxy interactions rather than AGN fuelling.
- ID:
- ivo://CDS.VizieR/J/ApJ/814/40
- Title:
- Nearby galaxy filaments with UV obs.
- Short Name:
- J/ApJ/814/40
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Simulations of the formation of large-scale structures predict that dark matter, low density highly ionized gas, and galaxies form 10 to 40Mpc scale filaments. These structures are easily recognized in the distribution of galaxies. Here we use Ly{alpha} absorption lines to study the gas in 30x6Mpc filament at cz~3500km/s, defined using a new catalog of nearby (cz<10000km/s) galaxies, which is complete down to a luminosity of about 0.05L_*_ for the region of space analyzed here. Using Hubble Space Telescope spectra of 24 active galactic nuclei, we sample the gas in this filament. All of our sightlines pass outside the virial radius of any known filament galaxy. Within 500kpc of the filament axis the detection rate is ~80%, but no detections are seen more than 2.1Mpc from the filament axis. The width of the Ly{alpha} lines correlates with filament impact parameter and the four BLAs in our sample occur within 400kpc of the filament axis, indicating increased temperature and/or turbulence. Comparing to simulations, we find that the recent Haardt & Madau extragalactic ionizing background predicts a factor of 3-5 too few ionizing photons. Using a more intense radiation field matches the hydrogen density profile within 2.1Mpc of the filament axis, but the simulations still overpredict the detection rate between 2.1 and 5Mpc from the axis. The baryonic mass inside filament galaxies is 1.4x10^13^M_{sun}_, while the mass of filament gas outside galaxy halos is found to be 5.2x10^13^M_{sun}_.
- ID:
- ivo://CDS.VizieR/J/A+A/649/A18
- Title:
- Nearby galaxy perspective on dust evolution
- Short Name:
- J/A+A/649/A18
- Date:
- 22 Feb 2022
- Publisher:
- CDS
- Description:
- The efficiency of the different processes responsible for the evolution of interstellar dust on the scale of a galaxy are, to date, very uncertain, spanning several orders of magnitude in the literature. Yet, precise knowledge of the grain properties is key to addressing numerous open questions about the physics of the interstellar medium and galaxy evolution. This article presents an empirical statistical study, aimed at quantifying the timescales of the main cosmic dust evolution processes as a function of the global properties of a galaxy. We have modelled a sample of ~800 nearby galaxies, spanning a wide range of metallicity, gas fraction, specific star formation rate and Hubble stage. We have derived the dust properties of each object from its spectral energy distribution. Throughout this paper, we have adopted a hierarchical Bayesian approach, resulting in a single large probability distribution of all the parameters of all the galaxies, to ensure the most rigorous interpretation of our data. We confirm the drastic evolution with metallicity of the dust-to-metal mass ratio (by two orders of magnitude), found by previous studies. We confirm the well-known evolution of the aromatic-feature-emitting grain mass fraction as a function of metallicity and interstellar radiation field intensity. Our data indicate the relation with metallicity is significantly stronger. Our results provide valuable constraints for simulations of galaxies. They imply that grain growth is the likely dust production mechanism in dusty high-redshift objects. We also emphasize the determinant role of local, low metallicity systems in order to address these questions.