- ID:
- ivo://CDS.VizieR/J/A+A/647/A152
- Title:
- Tully-Fisher relation in MAGIC groups
- Short Name:
- J/A+A/647/A152
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Galaxies in dense environments are subject to interactions and mechanisms that directly affect their evolution by lowering their gas fractions and consequently reducing their star-forming capacity earlier than their isolated counterparts. The aim of our project is to get new insights into the role of environment in the stellar and baryonic content of galaxies using a kinematic approach, through the study of the Tully-Fisher relation (TFR). We study a sample of galaxies in eight groups, over-dense by a factor larger than 25 with respect to the average projected density, spanning a redshift range of 0.5<z<0.8 and located in ten pointings of the MAGIC MUSE Guaranteed Time Observations program. We perform a morpho-kinematics analysis of this sample and set up a selection based on galaxy size, [OII]{lambda}{lambda}3727,3729 emission line doublet signal-to-noise ratio, bulge-to-disk ratio, and nuclear activity to construct a robust kinematic sample of 67 star-forming galaxies. We show that this selection considerably reduces the number of outliers in the TFR, which are predominantly dispersion-dominated galaxies. Similar to other studies, we find that including the velocity dispersion in the velocity budget mainly affects galaxies with low rotation velocities, reduces the scatter in the relation, increases its slope, and decreases its zero-point. Including gas masses is more significant for low-mass galaxies due to a larger gas fraction, and thus decreases the slope and increases the zero-point of the relation. Our results suggest a significant offset of the TFR zero-point between galaxies in low- and high-density environments, regardless of the kinematics estimator used. This can be interpreted as a decrease in either stellar mass by ~0.05-0.3dex or an increase in rotation velocity by ~0.02-0.06dex for galaxies in groups, depending on the samples used for comparison. We also studied the stellar and baryon mass fractions within stellar disks and found they both increase with stellar mass, the trend being more pronounced for the stellar component alone. These fractions do not exceed 50%. We show that this evolution of the TFR is consistent either with a decrease in star formation or with a contraction of the mass distribution due to the environment. These two effects probably act together, with their relative contribution depending on the mass regime.
Number of results to display per page
Search Results
- ID:
- ivo://CDS.VizieR/J/ApJ/607/665
- Title:
- Type Ia supernovae at z>1 discovered by HST
- Short Name:
- J/ApJ/607/665
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have discovered 16 Type Ia supernovae (SNe Ia) with the Hubble Space Telescope (HST) and have used them to provide the first conclusive evidence for cosmic deceleration that preceded the current epoch of cosmic acceleration. These objects, discovered during the course of the GOODS ACS Treasury program, include 6 of the 7 highest redshift SNe Ia known, all at z>1.25, and populate the Hubble diagram in unexplored territory. The luminosity distances to these objects and to 170 previously reported SNe Ia have been determined using empirical relations between light-curve shape and luminosity. A purely kinematic interpretation of the SN Ia sample provides evidence at the greater than 99% confidence level for a transition from deceleration to acceleration or, similarly, strong evidence for a cosmic jerk.
- ID:
- ivo://CDS.VizieR/J/A+A/581/A10
- Title:
- VEGAS: A VST Early-type GAlaxy Survey
- Short Name:
- J/A+A/581/A10
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the VST Early-type GAlaxy Survey (VEGAS), which is designed to obtain deep multiband photometry in g, r, i, of about one hundred nearby galaxies down to 27.3, 26.8, and 26mag/arcsec^2^ respectively, using the ESO facility VST/OmegaCAM. The goals of the survey are 1) to map the light distribution up to ten effective radii, r_e_; 2) to trace color gradients and surface brightness fluctuation gradients out to a few r_e_ for stellar population characterization; and 3) to obtain a full census of the satellite systems (globular clusters and dwarf galaxies) out to 20% of the galaxy virial radius. The external regions of galaxies retain signatures of the formation and evolution mechanisms that shaped them, and the study of nearby objects enables a detailed analysis of their morphology and interaction features. To clarify the complex variety of formation mechanisms of early-type galaxies (ETGs), wide and deep photometry is the primary observational step, which at the moment has been pursued with only a few dedicated programs. The VEGAS survey has been designated to provide these data for a volume-limited sample with exceptional image quality. In this commissioning photometric paper we illustrate the capabilities of the survey using g- and i-band VST/OmegaCAM images of the nearby galaxy NGC 4472 and of smaller ETGs in the surrounding field. Our surface brightness profiles reach rather faint levels and agree excellently well with previous literature. Genuine new results concern the detection of an intracluster light tail in NGC 4472 and of various substructures at increasing scales. We have also produced extended (g-i) color profiles. The VST/OmegaCAM data that we acquire in the context of the VEGAS survey provide a detailed view of substructures in the optical emission from extended galaxies, which can be as faint as a hundred times below the sky level.
- ID:
- ivo://CDS.VizieR/J/MNRAS/326/473
- Title:
- Vel. Distribution of low-luminosity E galaxies
- Short Name:
- J/MNRAS/326/473
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The shape of the line-of-sight velocity distribution (LOSVD) is measured for a sample of 14 elliptical galaxies, predominantly low-luminosity ellipticals. The sample is dominated by galaxies in the Virgo cluster but also contains ellipticals in nearby groups and low density environments. The parameterization of the LOSVD due to Gerhard and van der Marel & Franx is adopted, which measures the asymmetrical and symmetrical deviations of the LOSVD from a Gaussian by the amplitudes h3 and h4 of the Gauss-Hermite series. Rotation, velocity dispersion, h3 and h4 are determined as a function of radius for both major and minor axes using the Fourier Correlation Quotient method of Bender (1990). Galaxy spectra are rebinned in the direction of the spectroscopic slit to a minimum signal-to-noise ratio (S/N) of 60 per angstrom. Rotation and velocity dispersion are determined separately for S/N = 30 per angstrom.
- ID:
- ivo://CDS.VizieR/J/ApJ/368/54
- Title:
- Velocities and Photometry for E and S0 galaxies
- Short Name:
- J/ApJ/368/54
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- (Abstract from the paper) New spectroscopy and photometry have been obtained for 136 elliptical and S0 galaxies in the direction of the large-scale streaming flow attributed to the great attractor. Measurements of central velocity dispersion (sigma), total B magnitudes (B_T), the photometric parameter D_n, and the absorption-line index Mgi_2 are presented. Both internal and external comparisons indicate that measurements of log{sigma} are accurate to 0.05 dex, B_T to 0.15 mag, D_n to 0.015 dex, and Mg_2 to 0.017 mag. These data have been used in a previous paper by Dressler and Faber to estimate distances for these galaxies via the D_n - {sigma} relation. It is shown in this paper that the D_n - Mg_2 relation also predicts the same trends of peculiar velocity with distance, but with less accuracy. The relative accuracy of other distance indicators for elliptical galaxies is also discussed.
- ID:
- ivo://CDS.VizieR/J/ApJ/665/1067
- Title:
- Velocities in Cl 0024+16 and MS 0451-03
- Short Name:
- J/ApJ/665/1067
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We examine resolved spectroscopic data obtained with the Keck II telescope for 44 spheroidal galaxies in the fields of two rich clusters, Cl 0024+16 (z=0.40) and MS 0451-03 (z=0.54) and contrast this with similar data for 23 galaxies within the redshift interval 0.3<z<0.65 in the GOODS northern field. For each galaxy we examine the case for systemic rotation, derive central stellar velocity dispersions sigma and photometric ellipticities epsilon. Using morphological classifications obtained via Hubble Space Telescope imaging as the basis, we explore the utility of our kinematic quantities in distinguishing between pressure-supported ellipticals and rotationally supported lenticulars (S0s).
- ID:
- ivo://CDS.VizieR/J/A+AS/133/325
- Title:
- Velocities of 12 Fornax elliptical galaxies
- Short Name:
- J/A+AS/133/325
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present extended stellar kinematics for a sample of elliptical galaxies in the Fornax cluster. Out of the 13 galaxies presented here, five (FCC 119, FCC 136, NGC 1373, NGC 1428, FCC 335) have no previously published kinematical data. Major-axis velocity dispersion profiles (VDPs) and rotation curves (RCs) are given for 12 of the galaxies. A major feature of this data is the spatial extension: for 8 galaxies the data extends beyond 1R_e_, and for 5 it extends beyond 2R_e_. Compared to the previously available data, this corresponds to an increase in spatial coverage by a factor from 1 to 5. The present sample represents 86% of the ellipticals in Fornax brighter than B_T_=15mag.
- ID:
- ivo://CDS.VizieR/J/MNRAS/439/1015
- Title:
- Velocities of red giants in 7 LG dwarf galaxies
- Short Name:
- J/MNRAS/439/1015
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We measured velocities of 862 individual red giant stars in seven isolated dwarf galaxies in the Local Group: NGC 6822, IC 1613, VV 124 (UGC 4879), the Pegasus dwarf irregular galaxy (DDO 216), Leo A, Cetus, and Aquarius (DDO 210). We also computed velocity dispersions, taking into account the measurement uncertainties on individual stars. None of the isolated galaxies is denser than the densest Local Group satellite galaxy. Furthermore, the isolated dwarf galaxies have no obvious distinction in the velocity dispersion-half-light radius plane from the satellite galaxies of the Milky Way and M31. The similarity of the isolated and satellite galaxies' dynamics and structural parameters imposes limitations on environmental solutions to the too-big-to-fail problem, wherein there are fewer dense dwarf satellite galaxies than would be expected from cold dark matter simulations. This data set also has many other applications for dwarf galaxy evolution, including the transformation of dwarf irregular into dwarf spheroidal galaxies. We intend to explore these issues in future work.
- ID:
- ivo://CDS.VizieR/J/MNRAS/224/453
- Title:
- Velocity data of rich clusters
- Short Name:
- J/MNRAS/224/453
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present redshifts and stellar velocity dispersions for about 40 galaxies in each of 14 rich clusters from the southern cluster survey of Abell & Corwin (1983, Early Evolution of the Universe and Its Present Structure, p.179, Eds. Abell & Chincarini, Reidel, Dordrecht, Holland). The clusters cover a wide range of richnesses and Abell and Bautz-Morgan types, our aim being to compile a large, homogeneous database for examining and comparing dynamical phenomena and morphological properties. Further papers will present photometry for the clusters and an analysis of the database.
- ID:
- ivo://CDS.VizieR/J/ApJ/585/647
- Title:
- Velocity dispersion in AGN
- Short Name:
- J/ApJ/585/647
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- It has been proposed that the width of the narrow [O III] {lambda}5007 emission line can be used as a surrogate for the stellar velocity dispersion in active galaxies. This proposition is tested using the Sloan Digital Sky Survey (SDSS) Early Data Release (EDR) spectra of 107 low-redshift radio-quiet QSOs and Seyfert 1 galaxies by investigating the correlation between black hole mass, as determined from H{beta} FWHM and optical luminosity, and [O III] FWHM. The correlation is real, but the scatter is large. Without additional information or selection criteria, the [O III] width can predict the black hole mass to a factor of 5.
