- ID:
- ivo://CDS.VizieR/J/AJ/162/146
- Title:
- Kinematic and photometry of King 11 with Gaia EDR3
- Short Name:
- J/AJ/162/146
- Date:
- 21 Mar 2022 00:29:39
- Publisher:
- CDS
- Description:
- This paper presents an investigation of an old age open cluster King11 using Gaia's Early Data Release 3 data. Considering the stars with membership probability (P{mu})>90%, we identified 676 most probable cluster members within the cluster's limiting radius. The mean proper motion for King11 is determined as: {mu}x=-3.391{+/-}0.006 and {mu}y=-0.660{+/-}0.004mas/yr. The blue straggler stars of King11 show a centrally concentrated radial distribution. The values of limiting radius, age, and distance are determined as 18.51, 3.63{+/-}0.42Gyr, and 3.33{+/-}0.15kpc, respectively. The cluster's apex coordinates (A=267.84{+/-}1.01, D=-27.48{+/-}1.03) are determined using the apex diagram method and verified using the ({mu}U, {mu}T) diagram. We also obtained the orbit that the cluster follows in the Galaxy and estimated its tentative birthplace in the disk. The resulting spatial velocity of King 11 is 60.2{+/-}2.16km/s. A significant oscillation along the Z coordinate up to 0.556{+/-}0.022kpc is determined.
Number of results to display per page
Search Results
- ID:
- ivo://CDS.VizieR/J/other/ApSS/365.112
- Title:
- Kinematic data for high luminosity stars
- Short Name:
- J/other/ApSS/365
- Date:
- 22 Feb 2022
- Publisher:
- CDS
- Description:
- We calculated the median parallaxes for 47 OB associations including at least 10 stars with known Gaia DR2 parallaxes. A comparison between trigonometric and photometric parallaxes of OB associations reveals a zero-point offset of {Delta}_{pi}_=-0.11+/-0.04mas indicating that Gaia DR2 parallaxes are, on average, underestimated and the distances derived from them are overestimated. The correction of {Delta}_{pi}=-0.11 mas is consistent with the estimate that Arenou et al. (2018A&A...616A..17A) obtained for bright stars. An analysis of parallaxes of OB associations and high-luminosity field stars confirms our previous conclusion (Dambis et al., 2001AstL...27...58D) that the distance scale for OB stars established by Blaha and Humphreys (1989AJ.....98.1598B) must be reduced by 10-20%. Spurious systematic motions of 10-20km/s at the distances of 2-3kpc from the Sun are found to arise from the use of the uncorrected Gaia DR2 parallaxes.
- ID:
- ivo://CDS.VizieR/J/MNRAS/472/3887
- Title:
- Kinematic data for stars in OB-associations
- Short Name:
- J/MNRAS/472/3887
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use stellar proper motions from the catalog TGAS (2016, Cat. I/337) to study the kinematics of OB-associations identified by Blaha and Humphreys (1989AJ.....98.1598B). The TGAS proper motions of OB-associations generally agree well with the Hipparcos proper motions. The parameters of the Galactic rotation curve obtained with TGAS and Hipparcos proper motions agree within the errors. The average internal velocity dispersion calculated for 18 OB-associations with more than 10 TGAS stars is sigma_v_=3.9km/s, which is considerably smaller, by a factor of 0.4, than the velocity dispersions derived from Hipparcos data. The effective contribution from binary OB-stars into the velocity dispersion sigma_v inside OB-associations is sigma_b_=1.2km/s. The median virial and stellar masses of OB-associations are equal to 7.1x10^5^ and 9.0x10^3^M_{sun}_, respectively. Thus OB-associations must be unbound objects provided they do not include a lot of dense gas. The median star-formation efficiency is epsilon=2.1%. Nearly one third of stars of OB-associations must lie outside their tidal radius. We found that the Per OB1 and Car OB1 associations are expanding with the expansion started in a small region of 11-27pc 7-10Myr ago. The average expansion velocity is 6.3km/s.
- ID:
- ivo://CDS.VizieR/J/ApJ/829/108
- Title:
- Kinematic data of Galactic globular clusters
- Short Name:
- J/ApJ/829/108
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present mass and mass profile estimates for the Milky Way (MW) Galaxy using the Bayesian analysis developed by Eadie et al. (2015ApJ...806...54E) and using globular clusters (GCs) as tracers of the Galactic potential. The dark matter and GCs are assumed to follow different spatial distributions; we assume power-law model profiles and use the model distribution functions described in Evans et al. (1997MNRAS.286..315E) and Deason et al. (2012MNRAS.424L..44D). We explore the relationships between assumptions about model parameters and how these assumptions affect mass profile estimates. We also explore how using subsamples of the GC population beyond certain radii affect mass estimates. After exploring the posterior distributions of different parameter assumption scenarios, we conclude that a conservative estimate of the Galaxy's mass within 125kpc is 5.22x10^11^M_{sun}_, with a 50% probability region of (4.79,5.63)x10^11^M_{sun}_. Extrapolating out to the virial radius, we obtain a virial mass for the MW of 6.82x10^11^M_{sun}_ with 50% credible region of (6.06,7.53)x10^11^M_{sun}_ (r_vir_=185_-7_^+7^kpc). If we consider only the GCs beyond 10 kpc, then the virial mass is 9.02(5.69,10.86)x10^11^M_{sun}_ (r_vir_=198_-24_^+19^kpc). We also arrive at an estimate of the velocity anisotropy parameter {beta} of the GC population, which is {beta}=0.28 with a 50% credible region (0.21, 0.35). Interestingly, the mass estimates are sensitive to both the dark matter halo potential and visible matter tracer parameters, but are not very sensitive to the anisotropy parameter.
- ID:
- ivo://CDS.VizieR/J/ApJ/867/93
- Title:
- Kinematic data of YNMGs from RAVE & Gaia
- Short Name:
- J/ApJ/867/93
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The purpose of this study is the identification of young (1<age<100Myr), nearby (d<=100pc) moving groups (YNMGs) through their kinematic signature. YNMGs could be the result of the recent dispersal of young embedded clusters, such that they still represent kinematically cold groups, carrying the residual motion of their parental cloud. Using the fact that a large number (~14000) of the RAVE sources with evidence of chromospheric activity also present signatures of stellar youth, we selected a sample of solar-type sources with the highest probability of chromospheric activity to look for common kinematics. We made use of radial velocity information from RAVE and astrometric parameters from GAIA DR2 to construct a 6D position-velocity vector catalog for our full sample. We developed a method based on the grouping of stars with similar orientation of their velocity vectors, which we call the Cone Method Sampling. Using this method, we detected 646 sources with high significance in the velocity space, with respect to the average orientation of artificial distributions made from a purely Gaussian velocity ellipsoid with null vertex deviation. We compared this sample of highly significant sources with a catalog of YNMGs reported in previous studies, which yield 75 confirmed members. From the remaining sample, about 50% of the sources have ages younger than 100Myr, which indicate they are highly probable candidates to be new members of identified or even other YNMGs in the solar neighborhood.
- ID:
- ivo://CDS.VizieR/J/ApJ/783/131
- Title:
- Kinematic of stars in Galactic center
- Short Name:
- J/ApJ/783/131
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present new kinematic measurements and modeling of a sample of 116 young stars in the central parsec of the Galaxy in order to investigate the properties of the young stellar disk. The measurements were derived from a combination of speckle and laser guide star adaptive optics imaging and integral field spectroscopy from the Keck telescopes. Compared to earlier disk studies, the most important kinematic measurement improvement is in the precision of the accelerations in the plane of the sky, which have a factor of six smaller uncertainties ({sigma}~10{mu}as/yr2). We have also added the first radial velocity measurements for eight young stars, increasing the sample at the largest radii (6''-12'') by 25%. We derive the ensemble properties of the observed stars using Monte Carlo simulations of mock data. There is one highly significant kinematic feature (~20{sigma}), corresponding to the well-known clockwise disk, and no significant feature is detected at the location of the previously claimed counterclockwise disk. The true disk fraction is estimated to be ~20%, a factor of ~2.5 lower than previous claims, suggesting that we may be observing the remnant of what used to be a more densely populated stellar disk. The similarity in the kinematic properties of the B stars and the O/WR stars suggests a common star formation event. The intrinsic eccentricity distribution of the disk stars is unimodal, with an average value of <e> =0.27+/-0.07, which we show can be achieved through dynamical relaxation in an initially circular disk with a moderately top-heavy mass function.
- ID:
- ivo://CDS.VizieR/J/A+A/658/A22
- Title:
- Kinematic properties of white dwarfs
- Short Name:
- J/A+A/658/A22
- Date:
- 22 Feb 2022
- Publisher:
- CDS
- Description:
- Kinematic and chemical tagging of stellar populations have both revealed much information on the past and recent history of the Milky Way, including its formation history, merger events, and mixing of populations across the Galactic disk and halo. We present the first detailed 3D kinematic analysis of a sample of 3133 white dwarfs that used Gaia astrometry plus radial velocities, which were measured either by Gaia or by ground-based spectroscopic observations. The sample includes either isolated white dwarfs that have direct radial velocity measurements, or white dwarfs that belong to common proper motion pairs that contain nondegenerate companions with available radial velocities. A subset of common proper motion pairs also have metal abundances that have been measured by large-scale spectroscopic surveys or by our own follow-up observations. We used the white dwarfs as astrophysical clocks by determining their masses and total ages through interpolation with dedicated evolutionary models. We also used the nondegenerate companions in common proper motions to chemically tag the population. Combining accurate radial velocities with Gaia astrometry and proper motions, we derived the velocity components of our sample in the Galactic rest frame and their Galactic orbital parameters. The sample is mostly located within ~300 pc from the Sun. It predominantly contains (90-95%) thin-disk stars with almost circular Galactic orbits, while the remaining 5-10% of stars have more eccentric trajectories and belong to the thick disk. We identified seven isolated white dwarfs and two common proper motion pairs as halo members. We determined the age - velocity dispersion relation for the thin-disk members, which agrees with previous results that were achieved from different white dwarf samples without published radial velocities. The age - velocity dispersion relation shows signatures of dynamical heating and saturation after 4-6 Gyr. We observed a mild anticorrelation between [Fe/H] and the radial component of the average velocity dispersion, showing that dynamical mixing of populations takes place in the Galactic disk, as was detected through the analysis of other samples of FGK stars. We have shown that a white dwarf sample with accurate 3D kinematics and well-measured chemical compositions enables a wider understanding of their population in the solar neighborhood and its connection with the Galactic chemodynamics. The legacy of existing spectroscopic surveys will be boosted by the availability of upcoming larger samples of white dwarfs and common proper motion pairs with more uniform high-quality data.
- ID:
- ivo://CDS.VizieR/J/AJ/125/1397
- Title:
- Kinematics, age and abundances of open clusters
- Short Name:
- J/AJ/125/1397
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have compiled two new open cluster catalogs. In the first one, there are 119 objects with ages, distances, and metallicities available, while in the second one, 144 objects have both absolute proper motion and radial velocity data, of which 45 clusters also have metallicity data available.
- ID:
- ivo://CDS.VizieR/J/A+A/404/913
- Title:
- Kinematics and HR Diagrams of Southern Young Stars
- Short Name:
- J/A+A/404/913
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigate the spatial distribution, the space velocities and age distribution of the pre-main sequence (PMS) stars belonging to Ophiuchus, Lupus and Chamaeleon star-forming regions (SFRs), and of the young early-type star members of the Scorpius-Centaurus (Sco-Cen) OB association. These young stellar associations extend over the galactic longitude range from 280 to 360 degrees, and are at a distance interval of around 100 and 200pc. We present a compilation of PMS and early-type stars members of the investigated SFRs and OB associations. For these lists of stars we give the data used for the study of kinematic properties: positions, adopted distances, proper motions and radial velocities (whenever available), and the basic stellar data, used for the construction of Hertzsprung-Russel diagrams. All data have been taken from the literature. We also present the derived XYZ positions on the Galactic system, UVW components of the space velocities, visual extinction, and bolometric luminosity.
- ID:
- ivo://CDS.VizieR/J/ApJ/870/32
- Title:
- Kinematics in young star clusters & associations
- Short Name:
- J/ApJ/870/32
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Gaia mission has opened a new window into the internal kinematics of young star clusters at the sub-km/s level, with implications for our understanding of how star clusters form and evolve. We use a sample of 28 clusters and associations with ages from ~1-5Myr, where lists of members are available from previous X-ray, optical, and infrared studies. Proper motions from Gaia DR2 reveal that at least 75% of these systems are expanding; however, rotation is only detected in one system. Typical expansion velocities are on the order of ~0.5km/s, and in several systems, there is a positive radial gradient in expansion velocity. Systems that are still embedded in molecular clouds are less likely to be expanding than those that are partially or fully revealed. One-dimensional velocity dispersions, which range from {sigma}_1D_=1 to 3km/s, imply that most of the stellar systems in our sample are supervirial and that some are unbound. In star-forming regions that contain multiple clusters or subclusters, we find no evidence that these groups are coalescing, implying that hierarchical cluster assembly, if it occurs, must happen rapidly during the embedded stage.
