- ID:
- ivo://CDS.VizieR/J/ApJ/751/132
- Title:
- Keck observations of the Arches cluster
- Short Name:
- J/ApJ/751/132
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the first detection of the intrinsic velocity dispersion of the Arches cluster - a young (~2Myr), massive (10^4^M_{sun}_) starburst cluster located only 26pc in projection from the Galactic center. This was accomplished using proper motion measurements within the central 10"x10" of the cluster, obtained with the laser guide star adaptive optics system at Keck Observatory over a three-year time baseline (2006-2009). This uniform data set results in proper motion measurements that are improved by a factor ~5 over previous measurements from heterogeneous instruments. By careful, simultaneous accounting of the cluster and field contaminant distributions as well as the possible sources of measurement uncertainties, we estimate the internal velocity dispersion to be 0.15+/-0.01mas/yr, which corresponds to 5.4+/-0.4km/s at a distance of 8.4kpc. Collateral benefits of our data and analysis include: (1) cluster membership probabilities, which may be used to extract a clean-cluster sample for future photometric work; (2) a refined estimate of the bulk motion of the Arches cluster with respect to the field, which we find to be 172+/-15km/s, which is slightly slower than suggested by previous measurements using one epoch each with the Very Large Telescope and the Keck telescope; and (3) a velocity dispersion estimate for the field itself, which is likely dominated by the inner Galactic bulge and the nuclear disk.
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Search Results
- ID:
- ivo://CDS.VizieR/IV/34
- Title:
- K2 Ecliptic Plane Input Catalog (EPIC)
- Short Name:
- IV/34
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The K2 Mission (Howell+, 2014PASP..126..398H) uses the Kepler spacecraft to obtain high-precision photometry over ~80 day campaigns in the ecliptic plane. The Ecliptic Plane Input Catalog (EPIC) provides coordinates, photometry, and kinematics based on a federation of all-sky catalogs to support target selection and target management for the K2 mission.
263. Kepler Input Catalog
- ID:
- ivo://CDS.VizieR/V/133
- Title:
- Kepler Input Catalog
- Short Name:
- V/133
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Kepler Mission, NASA Discovery mission #10, is specifically designed to survey our region of the Milky Way galaxy to discover hundreds of Earth-size and smaller planets in or near the habitable zone and determine how many of the billions of stars in our galaxy have such planets. The KIC, or Kepler Input Catalog, is the primary source of information about objects observed as part of the ground-based Kepler Spectral Classification Program (SCP) in preparation for the selection of Kepler PI and GO targets. The KIC lists objects down to 21mag, but it is not complete to this limit. Light from only about 1/3 of these objects falls on the Kepler CCD detector. A small number of the KIC objects are calibration objects distributed across the sky. For this reason the full KIC should never be used for Kepler target selection.
- ID:
- ivo://CDS.VizieR/J/ApJS/225/10
- Title:
- Kinematic analysis of M7-L8 dwarfs
- Short Name:
- J/ApJS/225/10
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a kinematic analysis of 152 low surface gravity M7-L8 dwarfs by adding 18 new parallaxes (including 10 for comparative field objects), 38 new radial velocities, and 19 new proper motions. We also add low- or moderate-resolution near-infrared spectra for 43 sources confirming their low surface gravity features. Among the full sample, we find 39 objects to be high-likelihood or new bona fide members of nearby moving groups, 92 objects to be ambiguous members and 21 objects that are non-members. Using this age-calibrated sample, we investigate trends in gravity classification, photometric color, absolute magnitude, color-magnitude, luminosity, and effective temperature.
- 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.
- 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.
