- 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.
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- 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.
- ID:
- ivo://CDS.VizieR/J/ApJ/858/118
- Title:
- Kinematic data of 3 nearby low-mass galaxies
- Short Name:
- J/ApJ/858/118
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a detailed study of the nuclear star clusters (NSCs) and massive black holes (BHs) of four of the nearest low-mass early-type galaxies: M32, NGC 205, NGC 5102, and NGC 5206. We measure the dynamical masses of both the BHs and NSCs in these galaxies using Gemini/NIFS or VLT/SINFONI stellar kinematics, Hubble Space Telescope (HST) imaging, and Jeans anisotropic models. We detect massive BHs in M32, NGC 5102, and NGC 5206, while in NGC 205, we find only an upper limit. These BH mass estimates are consistent with previous measurements in M32 and NGC 205, while those in NGC 5102 and NGC 5206 are estimated for the first time and both found to be <10^6^M_{sun}_. This adds to just a handful of galaxies with dynamically measured sub-million M_{sun}_ central BHs. Combining these BH detections with our recent work on NGC 404's BH, we find that 80% (4/5) of nearby, low-mass (10^9^-10^10^M_{sun}_; {sigma}_*_~20-70km/s) early-type galaxies host BHs. Such a high occupation fraction suggests that the BH seeds formed in the early epoch of cosmic assembly likely resulted in abundant seeds, favoring a low-mass seed mechanism of the remnants, most likely from the first generation of massive stars. We find dynamical masses of the NSCs ranging from 2 to 73x10^6^M_{sun}_ and compare these masses to scaling relations for NSCs based primarily on photometric mass estimates. Color gradients suggest that younger stellar populations lie at the centers of the NSCs in three of the four galaxies (NGC 205, NGC 5102, and NGC 5206), while the morphology of two are complex and best fit with multiple morphological components (NGC 5102 and NGC 5206). The NSC kinematics show they are rotating, especially in M32 and NGC 5102 (V/{sigma}_*_~0.7).
- ID:
- ivo://CDS.VizieR/J/A+A/526/A114
- Title:
- Kinematic profiles of Virgo early-type galaxies
- Short Name:
- J/A+A/526/A114
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present new medium resolution kinematic data for a sample of 21 dwarf early-type galaxies (dEs) mainly in the Virgo cluster, obtained with the WHT and INT telescopes at the Roque de los Muchachos Observatory (La Palma, Spain). These data are used to study the origin of the dwarf elliptical galaxy population inhabiting clusters.
- ID:
- ivo://CDS.VizieR/J/ApJ/668/94
- Title:
- Kinematics across the Hubble sequence
- Short Name:
- J/ApJ/668/94
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The correlation between the maximum rotational velocity of the disk (vm) and the central stellar velocity dispersion of the bulge (sigma0) offers insights into the relationship between the halo and the bulge. We have assembled integrated HI line widths and central stellar velocity dispersions to study the vm-sigma0 relation for 792 galaxies spanning a broad range of Hubble types.
- ID:
- ivo://CDS.VizieR/J/A+A/424/447
- Title:
- Kinematics in 17 nearby spiral galaxies
- Short Name:
- J/A+A/424/447
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Ionized gas and stellar kinematics have been measured along the major axes of seventeen nearby spiral galaxies of intermediate to late morphological type. We discuss the properties of each sample galaxy, distinguishing between those characterized by regular or peculiar kinematics. In most of the observed galaxies, ionized gas rotates more rapidly than stars and has a lower velocity dispersion, as is to be expected if the gas is confined in the disc and supported by rotation while the stars are mostly supported by dynamical pressure. In a few objects, gas and stars show almost the same rotational velocity and low velocity dispersion, suggesting that their motion is dominated by rotation. Incorporating the spiral galaxies studied by Bertola et al. (1996ApJ...458L..67B), Corsini et al. (1999, Cat. <J/A+A/342/671>, 2003, Cat. <J/A+A/408/873>) and Vega Beltran et al. (2001, Cat. <J/A+A/374/394>) we have compiled a sample of 50 S0/a-Scd galaxies, for which the major-axis kinematics of the ionized gas and stars have been obtained with the same spatial (~1") and spectral (~50km/s) resolution, and measured with the same analysis techniques.
- ID:
- ivo://CDS.VizieR/J/ApJ/725/670
- Title:
- Kinematics in the M32 nucleus
- Short Name:
- J/ApJ/725/670
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using adaptive optics assisted Gemini/NIFS data, I study the present and past gas accretion in the central 3" of the M32 nucleus. From changes in the spectral slope and CO line depths near the center, I find evidence for unresolved dust emission resulting from black hole (BH) accretion. With a luminosity of ~2x10^38^erg/s, this dust emission appears to be the most luminous tracer of current BH accretion, 2 orders of magnitude more luminous than previously detected X-ray emission. These observations suggest that using high-resolution infrared data to search for dust emission may be an effective way to detect other nearby, low-luminosity BHs, such as those in globular clusters. I also examine the fossil evidence of gas accretion contained in the kinematics of the stars in the nucleus. The higher order moments (h3 and h4) of the line-of-sight velocity distribution show patterns that are remarkably similar to those seen on larger scales in elliptical galaxies and in gas-rich merger simulations. The kinematics suggests the presence of two components in the M32 nucleus, a dominant disk overlying a pressure supported component.
- ID:
- ivo://CDS.VizieR/J/MNRAS/432/998
- Title:
- Kinematics of Arp 270 (NGC 3395)
- Short Name:
- J/MNRAS/432/998
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have observed the Arp 270 system (NGC 3395 and NGC 3396) in H{alpha} emission using the Galaxy H{alpha} Fabry-Perot spectrometer on the 4.2m William Herschel Telescope (La Palma). In NGC 3396, which is edge-on to us, we detect gas inflow towards the centre, and also axially confined opposed outflows, characteristic of galactic superwinds, and we go on to examine the possibility that there is a shrouded AGN in the nucleus. The combination of surface brightness, velocity and velocity dispersion information enabled us to measure the radii, FWHM, and the masses of 108 HII regions in both galaxies.
1949. Kinematics of galaxies
- ID:
- ivo://CDS.VizieR/J/A+AS/127/117
- Title:
- Kinematics of galaxies
- Short Name:
- J/A+AS/127/117
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalogue of galaxies for which spatially resolved data on their internal kinematics have been published; there is no a priori restriction regarding their morphological type. The catalogue lists the references to the articles where the data are published, as well as a coded description of these data: observed emission or absorption line, velocity or velocity dispersion, radial profile or 2D field, observed position angle. This catalogue will be updated. Check for recent version at the URL: http://www-obs.univ-lyon1.fr/~prugniel/cgi-bin/hypercat/
- ID:
- ivo://CDS.VizieR/J/AJ/139/1871
- Title:
- Kinematics of globulars in NGC 5128
- Short Name:
- J/AJ/139/1871
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- New radial velocity measurements for previously known and newly confirmed globular clusters (GCs) in the nearby massive galaxy NGC 5128 are presented. We have obtained spectroscopy from LDSS-2/Magellan, VIMOS/Very Large Telescope, and HYDRA/Cerro Tololo Inter-American Observatory from which we have measured the radial velocities of 218 known, and identified 155 new, GCs. The current sample of confirmed GCs in NGC 5128 is now 605 with 563 of these having radial velocity measurements, the second largest kinematic database for any galaxy. We have performed a new kinematic analysis of the GC system that extends out to 45' in galactocentric radius. We have examined the systemic velocity, projected rotation amplitude and axis, and the projected velocity dispersion of the GCs as functions of galactocentric distance and metallicity.
