- ID:
- ivo://CDS.VizieR/J/AJ/126/2268
- Title:
- Velocity dispersions and Mg2 index of galaxies
- Short Name:
- J/AJ/126/2268
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present central velocity dispersions and Mg_2_ line indices for an all-sky sample of 1175 elliptical and S0 galaxies, of which 984 had no previous measures. This sample contains the largest set of homogeneous spectroscopic data for a uniform sample of elliptical galaxies in the nearby universe. These galaxies were observed as part of the ENEAR (Redshift-Distance Survey of Nearby Early-Type Galaxies) project, designed to study the peculiar motions and internal properties of the local early-type galaxies. Using 523 repeated observations of 317 galaxies obtained during different runs, the data are brought to a common zero point. These multiple observations, taken during the many runs and different instrumental setups employed for this project, are used to derive statistical corrections to the data and are found to be relatively small, typically <~5% of the velocity dispersion and 0.01mag in the Mg_2_ line strength. Typical errors are about 8% in velocity dispersion and 0.01mag in Mg_2_, in good agreement with values published elsewhere.
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Search Results
- ID:
- ivo://CDS.VizieR/J/A+AS/113/151
- Title:
- Velocity dispersions for elliptical galaxies
- Short Name:
- J/A+AS/113/151
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Measurements of central velocity dispersions and heliocentric radial velocities are presented for 94 field galaxies. Among these, 5 new radial velocities and 80 new central velocity dispersions are obtained. Reduction was performed independently by cross-correlation, Fourier-quotient and Fourier-correlation-quotient methods.
- ID:
- ivo://CDS.VizieR/J/ApJS/201/29
- Title:
- Velocity dispersions in active galaxies
- Short Name:
- J/ApJS/201/29
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We derive spatially resolved stellar kinematics for a sample of 84 out of 104 observed local (0.02<z<0.09) galaxies hosting type-1 active galactic nuclei (AGNs), based on long-slit spectra obtained at the 10m W. M. Keck-1 Telescope. In addition to providing central stellar velocity dispersions, we measure major axis rotation curves and velocity dispersion profiles using three separate wavelength regions, including the prominent Ca H&K, MgIb, and CaII NIR stellar features. In this paper, we compare kinematic measurements of stellar velocity dispersion obtained for different apertures, wavelength regions, and signal-to-noise ratios, and provide recipes to cross-calibrate the measurements reducing systematic effects to the level of a few percent. We also provide simple recipes based on readily observable quantities such as global colors and Ca H&K equivalent width that will allow observers of high-redshift AGN hosts to increase the probability of obtaining reliable stellar kinematic measurements from unresolved spectra in the region surrounding the Ca H&K lines.
- ID:
- ivo://CDS.VizieR/J/ApJ/724/714
- Title:
- Velocity dispersions of MS1054-03 & Coma galaxies
- Short Name:
- J/ApJ/724/714
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have measured velocity dispersions ({sigma}) for a sample of 36 galaxies with J<21.2 or M_r_<-20.6mag in MS 1054-03, a massive cluster of galaxies at z=0.83. Our data are of uniformly high quality down to our selection limit, our 16h exposures typically yielding errors of only {delta}({sigma})~10% for L* and fainter galaxies. By combining our measurements with data from the literature, we have 53 cluster galaxies with measured dispersions, and HST/ACS-derived sizes, colors and surface brightness. This sample is complete for the typical L^*^ galaxy at z~1, unlike most previous z~1 cluster samples which are complete only for the massive cluster members (>10^11^M_{sun}_). We find no evidence for a change in the tilt of the fundamental plane (FP).
- ID:
- ivo://CDS.VizieR/J/AJ/146/150
- Title:
- Velocity dispersions of 12 nearby galaxies
- Short Name:
- J/AJ/146/150
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a comprehensive study of the velocity dispersion of the atomic (HI) and molecular (H_2_) gas components in the disks (R{<~}R_25_) of a sample of 12 nearby spiral galaxies with moderate inclinations. Our analysis is based on sensitive high-resolution data from the THINGS (atomic gas) and HERACLES (molecular gas) surveys. To obtain reliable measurements of the velocity dispersion, we stack regions several kiloparsecs in size, after accounting for intrinsic velocity shifts due to galactic rotation and large-scale motions. We stack using various parameters: the galactocentric distance, star formation rate surface density, HI surface density, H_2_ surface density, and total gas surface density. We fit single Gaussian components to the stacked spectra and measure median velocity dispersions for HI of 11.9+/-3.1km/s and for CO of 12.0+/-3.9km/s. The CO velocity dispersions are thus, surprisingly, very similar to the corresponding ones of HI, with an average ratio of {sigma}_HI_/{sigma}_CO_=1.0+/-0.2 irrespective of the stacking parameter. The measured CO velocity dispersions are significantly higher (factor of ~2) than the traditional picture of a cold molecular gas disk associated with star formation. The high dispersion implies an additional thick molecular gas disk (possibly as thick as the HI disk). Our finding is in agreement with recent sensitive measurements in individual edge-on and face-on galaxies and points toward the general existence of a thick disk of molecular gas, in addition to the well-known thin disk in nearby spiral galaxies.
- ID:
- ivo://CDS.VizieR/J/other/NewA/27.41
- Title:
- Velocity distributions in galaxy clusters
- Short Name:
- J/other/NewA/27.
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study 416 galaxy systems with more than 7 members selected from the 2MASS catalog. We applied five well known normality tests to the velocity distributions of these systems to distinguish Gaussian and non-Gaussian clusters. Using controlled samples, we estimated type I and II errors for each test. We verified that individual tests minimize the chances of classifying a Gaussian system as non-Gaussian, while the Fisher's meta-analysis method, a procedure to combine p-values from several statistical tests, minimizes the chances of classifying a non-Gaussian system as Gaussian. Taking the positive elements of each method and also including a modality analysis of the velocity distribution, we defined objective criteria to split up the sample into Gaussian and non-Gaussian clusters. Our analysis indicates that 50-58% of groups have Gaussian distribution, a lower fraction than that we found using individual normality tests, 71-87%. We also found that some properties of galaxy clusters are significantly different between Gaussian and non-Gaussian systems. For instance, non-Gaussian clusters have larger radii and contain more galaxies than Gaussian clusters. Finally, we discussed the importance of choosing the adequate methodology to classify galaxy systems from their velocity distributions and also the dependence of the results on the criteria used to identify clusters in galaxy surveys.
- ID:
- ivo://CDS.VizieR/J/ApJ/670/105
- Title:
- Velocity profile of NGC 4151
- Short Name:
- J/ApJ/670/105
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a stellar dynamical estimate of the black hole (BH) mass in the Seyfert 1 galaxy, NGC 4151. We analyze ground-based spectroscopy as well as imaging data from the ground and space, and we construct three-integral axisymmetric models in order to constrain the BH mass and mass-to-light ratio.
- ID:
- ivo://CDS.VizieR/J/A+A/408/905
- Title:
- Very Luminous Galaxies
- Short Name:
- J/A+A/408/905
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The most luminous galaxies in the blue passband have a larger correlation amplitude than L* galaxies. They do not appear to be preferentially located in rich clusters or groups, but a significant fraction of them seem to be in systems which include fainter members. We present an analysis of fields centered on 18 Very Luminous Galaxies (M_B_<=-21) selected from the Southern Sky Redshift Survey 2 (Cat. <J/AJ/116/1>, based on new observations and public data of the 2dF Galaxy Redshift Survey (Cat. <VII/226>); we present also additional data on a CfA VLG and on Arp 127.
- ID:
- ivo://CDS.VizieR/J/ApJ/806/133
- Title:
- Virgo cluster ETGs: GC and galaxy diffuse light
- Short Name:
- J/ApJ/806/133
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a kinematic analysis of the globular cluster (GC) systems and diffuse stellar light of four intermediate luminosity (sub-L*) early-type galaxies in the Virgo cluster based on Gemini Multi-Object Spectrographs (GMOS) data. Our galaxy sample is fainter (-23.8<M_K_<-22.7) than most previous studies, nearly doubling the number of galaxies in this magnitude range that now have GC kinematics. The data for the diffuse light extends to 4R_e_, and the data for the GCs reaches 8-12R_e_. We find that the kinematics in these outer regions are all different despite the fact that these four galaxies have similar photometric properties, and are uniformly classified as "fast rotators" from their stellar kinematics within 1R_e_. The GC systems exhibit a wide range of kinematic morphology. The rotation axis and amplitude can change between the inner and outer regions, including a case of counter-rotation. This difference shows the importance of wide-field kinematic studies, and shows that stellar and GC kinematics can change significantly as one moves beyond the inner regions of galaxies. Moreover, the kinematics of the GC systems can differ from that of the stars, suggesting that the formation of the two populations are also distinct.
- ID:
- ivo://CDS.VizieR/J/ApJ/846/144
- Title:
- Virial analysis of the dense cores in Orion A
- Short Name:
- J/ApJ/846/144
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use data on gas temperature and velocity dispersion from the Green Bank Ammonia Survey and core masses and sizes from the James Clerk Maxwell Telescope Gould Belt Survey to estimate the virial states of dense cores within the Orion A molecular cloud. Surprisingly, we find that almost none of the dense cores are sufficiently massive to be bound when considering only the balance between self-gravity and the thermal and non-thermal motions present in the dense gas. Including the additional pressure binding imposed by the weight of the ambient molecular cloud material and additional smaller pressure terms, however, suggests that most of the dense cores are pressure-confined.
