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- ID:
- ivo://CDS.VizieR/J/A+AS/126/15
- Title:
- Kinematical data on early-type galaxies. II.
- Short Name:
- J/A+AS/126/15
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present new kinematical data for a sample of 38 early-type galaxies. Rotation curves and velocity-dispersion profiles are determined for 32 objects, while the central velocity dispersions are given for the whole sample. This is our second paper in a series devoted to the presentation of kinematical data on elliptical and S0 galaxies, derived from long-slit absorption spectroscopy.
- ID:
- ivo://CDS.VizieR/J/A+AS/126/519
- Title:
- Kinematical data on early-type galaxies. III.
- Short Name:
- J/A+AS/126/519
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present new kinematical data for a sample of 24 early-type galaxies. Rotation curves and velocity-dispersion profiles are determined for 21 objects, while the central velocity dispersions are given for the whole sample. This is our third paper in a series devoted to the presentation of kinematical data on elliptical and S0 galaxies, derived from long-slit absorption spectroscopy.
- ID:
- ivo://CDS.VizieR/J/A+AS/131/287
- Title:
- Kinematical data on early-type galaxies. IV.
- Short Name:
- J/A+AS/131/287
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present kinematical data for a sample of 25 galaxies. Rotation curves and velocity-dispersion profiles are determined for 16 objects, while the central velocity dispersions are given for the whole sample. This is our fourth paper in a series devoted to the presentation of kinematical data on elliptical and S0 galaxies, derived from long-slit absorption spectroscopy.
- ID:
- ivo://CDS.VizieR/J/A+AS/145/263
- Title:
- Kinematical data on early-type galaxies. V.
- Short Name:
- J/A+AS/145/263
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present kinematical data for a sample of 26 galaxies. Rotation curves and velocity-dispersion profiles are determined for all objects. This is our fifth paper in a series devoted to the presentation of data on elliptical and S0 galaxies, derived from long-slit absorption spectroscopy; the series now gathers 119 galaxies with homogeneous data.
- ID:
- ivo://CDS.VizieR/J/A+A/384/371
- Title:
- Kinematical data on early-type galaxies. VI
- Short Name:
- J/A+A/384/371
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the result of spectroscopic observations of a sample of 73 galaxies, completing the database published in this series of articles. The sample contains mostly low-luminosity early-type objects, including four dwarfs of the Local Group (in particular, deep spectra of NGC 205), 15 dEs or dS0s in the Virgo cluster, and UGC 05442, a spheroidal dwarf of the M81 group. We have measured the central velocity dispersion for all but one object, and determined the major-axis rotation and velocity-dispersion profiles for 59 objects. For the current sample of diffuse (or dwarf) elliptical galaxies, we have compared stellar rotation to velocity dispersion; the analysis suggests that these objects may be nearly rotationally flattened, and therefore that anisotropy may be less important than previously thought.
- ID:
- ivo://CDS.VizieR/J/A+AS/110/19
- Title:
- Kinematical observations of pairs of galaxies
- Short Name:
- J/A+AS/110/19
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present new radial velocities for 203 galaxies in 105 pairs and 2 triplets. The majority are close pairs of early-type galaxies; there are also pairs including a giant spiral galaxy (generally M51 type), and a few are wide pairs of early-type galaxies. Most velocities were measured from the absorption lines in the region of Mgb; emission-line velocities are also given for 22 galaxies. The velocity of one component only was measured in 13 (generally hierarchical) pairs. Velocity dispersions were measured for a subsample of 18 close pairs of early-type galaxies.
- ID:
- ivo://CDS.VizieR/J/A+A/593/A40
- Title:
- Kinematical profiles of nearby galaxies
- Short Name:
- J/A+A/593/A40
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the largest catalog of detailed stellar kinematics of the central parts of nearby galaxies, which includes higher moments of the line-of-sight velocity distribution (LOSVD) function represented by the Gauss-Hermite series. The kinematics is measured on a sample of galaxies selected from the Arecibo Legacy Fast ALFA (Alfalfa) survey using spectroscopy from the Sloan Digital Sky Survey (SDSS DR7). The SDSS DR7 offers measurements of the LOSVD based on the assumption of a pure Gaussian shape of the broadening function caused by the combination of rotational and random motion of the stars in galaxies. We discuss the consequences of this oversimplification since the velocity dispersion, one of the measured quantities, often serves as the proxy to important modeling parameters such as the black-hole mass and the virial mass of galaxies. The publicly available pPXF code is used to calculate the full kinematical profile for the sample galaxies including higher moments of their LOSVD. Both observed and synthetic stellar libraries were used and the related template mismatch problem is discussed. For the whole sample of 2180 nearby galaxies reflecting morphological distribution characteristic for the local Universe, we successfully recovered stellar kinematics of their central parts, including higher order moments of the LOSVD function, for signal-to-noise above 50.
- ID:
- ivo://CDS.VizieR/J/ApJ/768/172
- Title:
- Kinematic analysis of red giant in M31 dSphs
- Short Name:
- J/ApJ/768/172
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a homogeneous kinematic analysis of red giant branch stars within 18 of the 28 Andromeda dwarf spheroidal (dSph) galaxies, obtained using the Keck I/LRIS and Keck II/DEIMOS spectrographs. Based on their g-i colors (taken with the CFHT/MegaCam imager), physical positions on the sky, and radial velocities, we assign probabilities of dSph membership to each observed star. Using this information, the velocity dispersions, central masses, and central densities of the dark matter halos are calculated for these objects, and compared with the properties of the Milky Way dSph population. We also measure the average metallicity ([Fe/H]) from the co-added spectra of member stars for each M31 dSph and find that they are consistent with the trend of decreasing [Fe/H] with luminosity observed in the Milky Way population. We find that three of our studied M31 dSphs appear as significant outliers in terms of their central velocity dispersion, And XIX, XXI, and XXV, all of which have large half-light radii (>~700pc) and low velocity dispersions ({sigma}_v_<5km/s). In addition, And XXV has a mass-to-light ratio within its half-light radius of just [M/L]_half_=10.3_-6.7_^7.0^, making it consistent with a simple stellar system with no appreciable dark matter component within its 1{sigma} uncertainties. We suggest that the structure of the dark matter halos of these outliers have been significantly altered by tides.
- ID:
- ivo://CDS.VizieR/J/ApJ/777/42
- Title:
- Kinematic and HI data for the NFGS
- Short Name:
- J/ApJ/777/42
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We relate transitions in galaxy structure and gas content to refueling, here defined to include both the external gas accretion and the internal gas processing needed to renew reservoirs for star formation. We analyze two z=0 data sets: a high-quality ~200 galaxy sample (the Nearby Field Galaxy Survey, data release herein) and a volume-limited ~3000 galaxy sample with reprocessed archival data. Both reach down to baryonic masses ~10^9^M_{sun}_ and span void-to-cluster environments. Two mass-dependent transitions are evident: (1) below the "gas-richness threshold" scale (V~125km/s), gas-dominated quasi-bulgeless Sd-Im galaxies become numerically dominant; while (2) above the "bimodality" scale (V~200km/s), gas-starved E/S0s become the norm. Notwithstanding these transitions, galaxy mass (or V as its proxy) is a poor predictor of gas-to-stellar mass ratio M_gas_/M_*_. Instead, M_gas_/M_*_ correlates well with the ratio of a galaxy's stellar mass formed in the last Gyr to its preexisting stellar mass, such that the two ratios have numerically similar values. This striking correspondence between past-averaged star formation and current gas richness implies routine refueling of star-forming galaxies on Gyr timescales. We argue that this refueling underlies the tight M_gas_/M_*_ versus color correlations often used to measure "photometric gas fractions." Furthermore, the threshold and bimodality scale transitions reflect mass-dependent demographic shifts between three refueling regimes--accretion-dominated, processing-dominated, and quenched. In this picture, gas-dominated dwarfs are explained not by inefficient star formation but by overwhelming gas accretion, which fuels stellar mass doubling in <~1Gyr. Moreover, moderately gas-rich bulged disks such as the Milky Way are transitional, becoming abundant only in the narrow range between the threshold and bimodality scales.