- ID:
- ivo://CDS.VizieR/J/ApJ/896/100
- Title:
- Kinematic structure of the Galactic Center S cluster
- Short Name:
- J/ApJ/896/100
- Date:
- 11 Mar 2022
- Publisher:
- CDS
- Description:
- We present a detailed analysis of the kinematics of 112 stars that mostly comprise the high-velocity S cluster and orbit the supermassive black hole Sgr A* at the center of the Milky Way. For 39 of them, orbital elements are known; for the remainder, we know proper motions. The distribution of the inclinations and the proper motion flight directions deviate significantly from a uniform distribution, which one expects if the orientation of the orbits are random. Across the central arcseconds, the S-cluster stars are arranged in two almost edge-on disks that are located at a position angle approximately +/-45{deg} with respect to the Galactic plane. The angular momentum vectors for stars in each disk point in both directions, i.e., the stars in a given disk rotate in opposite ways. The poles of this structure are located only about 25{deg} from the line of sight. This structure may be the result of a resonance process that started with the formation of the young B-dwarf stars in the cluster about 6Myr ago. Alternatively, it indicated the presence of a disturber at a distance from the center comparable to the distance of the compact stellar association IRS 13.
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- ID:
- ivo://CDS.VizieR/J/MNRAS/407/2109
- Title:
- Kinematic study of open clusters
- Short Name:
- J/MNRAS/407/2109
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Galactic population of open clusters provides an insight into star formation in the Galaxy. The open cluster catalogue by Dias et al. (Cat. B/ocl) is a rich source of data, including kinematic information. This large sample made it possible to carry out a systematic analysis of 481 open cluster orbits, using parameters based on orbit eccentricity and separation from the Galactic plane. These two parameters may be indicative of origin, and we find them to be correlated. We also find them to be correlated with metallicity, another parameter suggested elsewhere to be a marker for origin in that high values of any of these two parameters generally indicate a low metallicity ([Fe/H]solar<-0.2dex). The resulting analysis points to four open clusters in the catalogue being of extragalactic origin by impact of high-velocity cloud on the disc: Berkeley 21, 32, 99 and Melotte 66, with a possible further four due to this origin (NGC 2158, 2420, 7789 and IC 1311). A further three may be due to Galactic globular cluster impact on the disc, i.e. of internal Galactic origin (NGC 6791, 1817 and 7044).
- ID:
- ivo://CDS.VizieR/J/ApJ/836/202
- Title:
- Kinematic study of the Leo II dwarf galaxy
- Short Name:
- J/ApJ/836/202
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We conducted a large spectroscopic survey of 336 red giants in the direction of the Leo II dwarf galaxy using Hectochelle on the Multiple Mirror Telescope, and we conclude that 175 of them are members based on their radial velocities and surface gravities. Of this set, 40 stars have never before been observed spectroscopically. The systemic velocity of the dwarf is 78.3+/-0.6km/s with a velocity dispersion of 7.4+/-0.4km/s. We identify one star beyond the tidal radius of Leo II but find no signatures of uniform rotation, kinematic asymmetries, or streams. The stars show a strong metallicity gradient of -1.53+/-0.10dex/kpc and have a mean metallicity of -1.70+/-0.02dex.
- ID:
- ivo://CDS.VizieR/J/MNRAS/369/120
- Title:
- Kinematic survey of planetary nebulae in M31
- Short Name:
- J/MNRAS/369/120
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalogue of positions, magnitudes and velocities for 3300 emission-line objects found by the Planetary Nebula Spectrograph in a survey of the Andromeda galaxy, M31. Of these objects, 2615 are found likely to be planetary nebulae (PNe) associated with M31. The survey area covers the whole of M31's disc out to a radius of 1.5{deg}. Beyond this radius, observations have been made along the major and minor axes, and the Northern Spur and Southern Stream regions. The calibrated data have been checked for internal consistency and compared with other catalogues. With the exception of the very central, high surface brightness region of M31, this survey is complete to a magnitude limit of m5007~23.75, 3.5mag into the PN luminosity function.
- ID:
- ivo://CDS.VizieR/J/MNRAS/442/3544
- Title:
- Kinematic tracers in Umbrella galaxy (NGC4651)
- Short Name:
- J/MNRAS/442/3544
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study the dynamics of faint stellar substructures around the Umbrella Galaxy, NGC 4651, which hosts a dramatic system of streams and shells formed through the tidal disruption of a nucleated dwarf elliptical galaxy. We elucidate the basic characteristics of the system (colours, luminosities, stellar masses) using multiband Subaru/Suprime-Cam images. The implied stellar mass ratio of the ongoing merger event is ~1:50. We identify candidate kinematic tracers (globular clusters, planetary nebulae, HII regions) and follow up a subset with Keck/DEIMOS (DEep Imaging Multi-object Spectrograph) spectroscopy to obtain velocities. We find that 15 of the tracers are likely associated with halo substructures, including the probable stream progenitor nucleus. These objects delineate a kinematically cold feature in position-velocity phase space. We model the stream using single test particle orbits, plus a rescaled pre-existing N-body simulation. We infer a very eccentric orbit with a period of ~0.35Gyr and turning points at ~2-4 and ~40kpc, implying a recent passage of the satellite through the disc, which may have provoked the visible disturbances in the host galaxy. This work confirms that the kinematics of low surface brightness substructures can be recovered and modelled using discrete tracers - a breakthrough that opens up a fresh avenue for unravelling the detailed physics of minor merging.
- ID:
- ivo://CDS.VizieR/J/A+A/576/A33
- Title:
- KINGFISH galaxy sample radial profile SED
- Short Name:
- J/A+A/576/A33
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Physical conditions of the interstellar medium in galaxies are closely linked to the ambient radiation field and the heating of dust grains. In order to characterize dust properties in galaxies over a wide range of physical conditions, we present here the radial surface brightness profiles of the entire sample of 61 galaxies from Key Insights into Nearby Galaxies: Far-Infrared Survey with Herschel (KINGFISH). The main goal of our work is the characterization of the grain emissivities, dust temperatures, and interstellar radiation fields responsible for heating the dust. After fitting the dust and stellar radial profiles with exponential functions, we fit the far-infrared spectral energy distribution (SED) in each annular region with single-temperature modified black bodies using both variable (MBBV) and fixed (MBBF) emissivity indices {beta}, as well as with physically motivated dust models. Results show that while most SED parameters decrease with radius, the emissivity index {beta} also decreases with radius in some galaxies, but in others is increasing, or rising in the inner regions and falling in the outer ones. Despite the fixed grain emissivity (average {beta}~2.1) of the physically-motivated models, they are well able to accommodate flat spectral slopes with {beta}<=1. We find that flatter slopes ({beta}<=1.5) are associated with cooler temperatures, contrary to what would be expected from the usual T_dust_-{beta} degeneracy. This trend is related to variations in Umin since {beta} and U_min_ are very closely linked over the entire range in U_min_ sampled by the KINGFISH galaxies: low U_min_ is associated with flat {beta}<=1. Both these results strongly suggest that the low apparent {beta} values (flat slopes) in MBBV fits are caused by temperature mixing along the line-of-sight, rather than by intrinsic variations in grain properties.
- ID:
- ivo://CDS.VizieR/J/BaltA/19/197
- Title:
- King 7 Vilnius photometry
- Short Name:
- J/BaltA/19/197
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of CCD photometry in the seven-color Vilnius system for 1549 stars down to V=16mag in a 1.5 square degree field around the cluster King 7, at the Perseus and Camelopardalis border. Using photometric parameters, two-dimensional spectral types, interstellar extinctions and distances for most of the stars are determined.
- ID:
- ivo://CDS.VizieR/J/AJ/162/224
- Title:
- King 7 Vilnius photometry. II. Extinctions
- Short Name:
- J/AJ/162/224
- Date:
- 15 Mar 2022
- Publisher:
- CDS
- Description:
- Interstellar extinction in two concentric square areas of the sizes 1.25x1.25deg^2^ and 0.2x0.2deg^2^ in the direction of open cluster King7 is investigated applying two-dimensional photometric classification of stars observed in the Vilnius seven-color photometric system down to V=15.5mag (1084 stars) and 19.5mag (584 stars), respectively. The cluster members (284 stars) are identified applying their coordinates, proper motions, and parallaxes taken from the Gaia EDR3 catalog. New parameters of the cluster (distance, diameter, interstellar extinction, and age) are obtained. Photogeometric distances of stars are taken from Bailer-Jones et al. (2021) based on the Gaia parallaxes from EDR3. Physically the cluster is located at the outer edge of the Perseus spiral arm at d=2.74kpc, its diameter is 9.6pc, the age is 175{+/-}25Myr, the earliest stars are of spectral classes B6-B7. The average interstellar extinction A_V_=4.24mag. From the radial velocities of CO and the Galactic rotation curve we estimate distances to the nearby dust clouds TGU H989 P2 and P3 at 650-670pc from the Sun.
- ID:
- ivo://CDS.VizieR/J/AJ/161/176
- Title:
- KISOGP: 7055 eclipsing binaries with KWFC
- Short Name:
- J/AJ/161/176
- Date:
- 09 Mar 2022 22:00:00
- Publisher:
- CDS
- Description:
- We present a catalog of eclipsing binaries in the northern Galactic plane from the Kiso Wide-Field Camera Intensive Survey of the Galactic Plane (KISOGP). We visually identified 7055 eclipsing binaries spread across ~330deg^2^, including 4197 W Ursa Majoris/EW-type, 1458 {beta}Lyrae/EB-type, and 1400 Algol/EA-type eclipsing binaries. For all systems, I-band light curves were used to obtain accurate system parameters. We derived the distances and extinction values for the EW-type objects from their period-luminosity relation. We also obtained the structure of the thin disk from the distribution of our sample of eclipsing binary systems, combined with those of high-mass star-forming regions and Cepheid tracers. We found that the thin disk is inhomogeneous in number density as a function of Galactic longitude. Using this new set of distance tracers, we constrain the detailed structure of the thin disk. Finally, we report a global parallax zero-point offset of {Delta}{pi}=-42.1{+/-}1.9(stat.){+/-}12.9(syst.){mu}as between our carefully calibrated EW-type eclipsing binary positions and those provided by Gaia Early Data Release 3. Implementation of the officially recommended parallax zero-point correction results in a significantly reduced offset. Additionally, we provide a photometric characterization of our EW-type eclipsing binaries that can be applied to further analyses.
- ID:
- ivo://CDS.VizieR/VII/179A
- Title:
- Kiso Survey for UV-Excess Galaxies. XVIII
- Short Name:
- VII/179A
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The already published catalogue series I - XVII of the KUGs (Kiso Ultraviolet-excess Galaxies) has now covered the sky area of some 5,100 square degrees. The number of the KUGs detected is in total 8,968, giving the number density of 1.8 per square degree. After deleting the objects which appear repeatedly in some neighbouring survey areas, the net count of the KUGs results in 8,162. This may be an appropriate sample number for making some statistical study of the KUG, although the sky coverage is not yet sufficient. This catalog presents a merged version of the 17 catalogues, where all KUGs are arranged in order of the right ascension, for the convenience of users.