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16781. Velocities of {lambda} Bootis stars
ID:
ivo://CDS.VizieR/J/A+A/412/447
Title:
Velocities of {lambda} Bootis stars
Short Name:
J/A+A/412/447
Date:
21 Oct 2021
Publisher:
CDS
Description:
We demonstrate that it is arduous to define the {lambda} Boo stars as a class of objects exhibiting uniform abundance peculiarities which would be generated by a mechanism altering the structure of their atmospheric layers. We collected the stars classified as {lambda} Boo up to now and discuss their properties, in particular the important percentage of confirmed binaries producing composite spectra (including our adaptive optics observations) and of misclassified objects. The unexplained RV variables (and thus suspected binaries), the known SB for which we lack information on the companion, the stars with an UV flux inconsistent with their classification, and the fast rotating stars for which no accurate abundance analysis can be performed, are also reviewed.
16782. Velocities of M67 main-sequence and giant stars
ID:
ivo://CDS.VizieR/J/A+A/526/A127
Title:
Velocities of M67 main-sequence and giant stars
Short Name:
J/A+A/526/A127
Date:
21 Oct 2021
Publisher:
CDS
Description:
Precise analyses of stellar radial velocities is able to reveal intrinsic causes of the wavelength shifts of spectral lines (other than Doppler shifts due to radial motion), such as gravitational redshifts and convective blueshifts. Aims. Gravitational redshifts in solar-type main-sequence stars are expected to be some 500m/s greater than those in giants. We search for this difference in redshifts among groups of open-cluster stars that share the same average space motion and thus have the same average Doppler shift.
16783. Velocities of 43 nearby L dwarfs
ID:
ivo://CDS.VizieR/J/A+A/512/A37
Title:
Velocities of 43 nearby L dwarfs
Short Name:
J/A+A/512/A37
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present radial velocity measurements of a sample of L0-L8 dwarfs observed with VLT/UVES and Keck/HIRES. We combine these measurements with distance and proper motion from the literature to determine space motions for 43 of our targets. We identify nine candidate members of young moving groups, which have ages of 50-600Myr according to their space motion.
16784. Velocities of NGC 4636 globular clusters
ID:
ivo://CDS.VizieR/J/A+A/544/A115
Title:
Velocities of NGC 4636 globular clusters
Short Name:
J/A+A/544/A115
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present new radial velocities for 289 globular clusters around NGC 4636, the southernmost giant elliptical galaxy of the Virgo cluster. The data were obtained with FORS2/MXU at the Very Large Telescope. Together with data analysed in an earlier study, we now have a sample of 460 globular cluster velocities out to a radius of 12-arcmin (60kpc) available - one of the largest of its kind. This new data set also provides a much more complete angular coverage. Moreover, we present new kinematical data of the inner stellar population of NGC 4636. We perform an updated Jeans analysis, using both stellar and GC data, to better constrain the dark halo properties.
16785. Velocities of NGC 1399 globular clusters
ID:
ivo://CDS.VizieR/J/A+A/513/A52
Title:
Velocities of NGC 1399 globular clusters
Short Name:
J/A+A/513/A52
Date:
21 Oct 2021
Publisher:
CDS
Description:
Globular clusters (GCs) are tracers of the gravitational potential of their host galaxies. Moreover, their kinematic properties may provide clues for understanding the formation of GC systems and their host galaxies. We use the largest set of GC velocities obtained so far of any elliptical galaxy to revise and extend the previous investigations (Richtler et al., 2004AJ....127.2094R) of the dynamics of NGC 1399, the central dominant galaxy of the nearby Fornax cluster of galaxies. The GC velocities are used to study the kinematics, their relation with population properties, and the dark matter halo of NGC 1399. We have obtained 477 new medium-resolution spectra (of these, 292 are spectra from 265 individual GCs, 241 of which are not in the previous data set). with the VLT FORS 2 and Gemini South GMOS multi--object spectrographs. We revise velocities for the old spectra and measure velocities for the new spectra, using the same templates to obtain an homogeneously treated data set. Our entire sample now comprises velocities for almost 700 GCs with projected galactocentric radii between 6 and 100kpc. In addition, we use velocities of GCs at larger distances published by Bergond et al. (2007, Cat. J/A+A/464/L21). Combining the kinematic data with wide-field photometric Washington data, we study the kinematics of the metal-poor and metal--rich subpopulations. We discuss in detail the velocity dispersions of subsamples and perform spherical Jeans modelling.
16786. Velocities of NGC 1023 planetary nebulae
ID:
ivo://CDS.VizieR/J/MNRAS/384/943
Title:
Velocities of NGC 1023 planetary nebulae
Short Name:
J/MNRAS/384/943
Date:
21 Oct 2021
Publisher:
CDS
Description:
We investigate the manner in which lenticular galaxies are formed by studying their stellar kinematics: an S0 formed from a fading spiral galaxy should display similar cold outer disc kinematics to its progenitor, while an S0 formed in a minor merger should be more dominated by random motions. In a pilot study to attempt to distinguish between these scenarios, we have measured the planetary nebula (PN) kinematics of the nearby S0 system NGC 1023. Using the Planetary Nebula Spectrograph, we have detected and measured the line-of-sight velocities of 204 candidate PNe in the field of this galaxy. Out to intermediate radii, the system displays the kinematics of a normal rotationally-supported disc system. After correction of its rotational velocities for asymmetric drift, the galaxy lies just below the spiral galaxy Tully-Fisher relation, as one would expect for a fading system. However, at larger radii the kinematics undergo a gradual but major transition to random motion with little rotation. This transition does not seem to reflect a change in the viewing geometry or the presence of a distinct halo component, since the number counts of PNe follow the same simple exponential decline as the stellar continuum with the same projected disc ellipticity out to large radii. The galaxy's small companion, NGC 1023A, does not seem to be large enough to have caused the observed modification either. This combination of properties would seem to indicate a complex evolutionary history in either the transition to form an S0 or in the past life of the spiral galaxy from which the S0 formed. More data sets of this type from both spirals and S0s are needed in order to definitively determine the relationship between these types of system.
16787. Velocities of OMC-1 flows
ID:
ivo://CDS.VizieR/J/A+A/466/949
Title:
Velocities of OMC-1 flows
Short Name:
J/A+A/466/949
Date:
21 Oct 2021
Publisher:
CDS
Description:
Observations are reported of H_2_ IR emission in the S(1) v=1-0 line at 2.121{mu}m in the Orion Molecular Cloud, OMC1, using the GriF instrument on the Canada-France-Hawaii Telescope. GriF uses a combination of adaptive optics and Fabry-Perot interferometry, yielding a spatial resolution of 0.15" to 0.18" and velocity discrimination as high as 1km/s. 193 bright H_2_ emission regions can be identified in OMC1. The general characteristics of these features are described in terms of radial velocities, brightness and spatial displacement of maxima of velocity and brightness, the latter to yield the orientation of flows in the plane of the sky. Strong spatial correlation between velocity and bright H_2_ emission is found and serves to identify many features as shocks.
16788. Velocities of Planetary Nebula in 5 galaxies
ID:
ivo://CDS.VizieR/J/A+A/549/A115
Title:
Velocities of Planetary Nebula in 5 galaxies
Short Name:
J/A+A/549/A115
Date:
21 Oct 2021
Publisher:
CDS
Description:
The origins of S0 galaxies remain obscure, with various mechanisms proposed for their formation, likely depending on environment. These mechanisms would imprint different signatures in the galaxies' stellar kinematics out to large radii, offering a method for distinguishing between them. We aim to study a sample of six S0 galaxies from a range of environments, and use planetary nebulae (PNe) as tracers of their stellar populations out to very large radii, to determine their kinematics in order to understand their origins. Using a special-purpose instrument, the Planetary Nebula Spectrograph, we observe and extract PNe catalogues for these six systems. We show that the PNe have the same spatial distribution as the starlight, that the numbers of them are consistent with what would be expected in a comparable old stellar population in elliptical galaxies, and that their kinematics join smoothly onto those derived at smaller radii from conventional spectroscopy. The high-quality kinematic observations presented here form an excellent set for studying the detailed kinematics of S0 galaxies, in order to unravel their formation histories. We find that PNe are good tracers of stellar kinematics in these systems. We show that the recovered kinematics are largely dominated by rotational motion, although with significant random velocities in most cases.
16789. Velocities of PNe in NGC 4697
ID:
ivo://CDS.VizieR/J/ApJ/691/228
Title:
Velocities of PNe in NGC 4697
Short Name:
J/ApJ/691/228
Date:
21 Oct 2021
Publisher:
CDS
Description:
We describe the implementation of slitless radial velocity measurements of extragalactic planetary nebulae (PNs) with the 8.2m Subaru telescope and its Cassegrain imaging spectrograph, Faint Object Camera and Spectrograph (FOCAS). As a first application, we have extended a previous search for PNs in NGC 4697 to larger angular distances from its center. A total of 218 PNs were detected, and their radial velocities were measured. We have added 56 new PN detections to the existing sample of 535, observed previously with the ESO VLT + FORS imaging spectrograph; 36 of these new 56 PNs are located at angular distances larger than 230 arcsec from the center of NGC 4697. We compare the new FOCAS velocities with the earlier FORS velocities, for 158 of the 162 reobserved sources, finding good agreement. We now have kinematic information extending out to five effective radii from the center.
16790. Velocities of Popother/.II binray stars
ID:
ivo://CDS.VizieR/J/AN/323/139
Title:
Velocities of Popother/.II binray stars
Short Name:
J/AN/323/139
Date:
21 Oct 2021
Publisher:
CDS
Description:
Radial velocities for 114 Hipparcos stars, mostly high transverse velocity binaries without previous radial velocity measurement, are published. Measurements are made with the CORAVEL-type radial velocity spectrometer. The accuracy of measurements is better than 1km/s. Two stars, BD+30 2129A and HD 117466AB are found to be radial velocity variables, and three more stars, HD 119515A, HD 131597AB, and HD 153344, are possible radial velocity variables.

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