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4491. Velocities and CMT2 photometry in globular M92
ID:
ivo://CDS.VizieR/J/AJ/133/1041
Title:
Velocities and CMT2 photometry in globular M92
Short Name:
J/AJ/133/1041
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report the determination of high-accuracy radial velocities for 306 members of the globular cluster M92 using the Hydra multiobject spectrograph on the WIYN telescope. We have concentrated on stars outside of the central region of the cluster, located up to 14.4' from the cluster center. Candidate members were selected for spectroscopy based on a photometric metallicity index determined from three-band Washington photometry, also obtained with the WIYN telescope.
4492. Velocities and Photometry for E and S0 galaxies
ID:
ivo://CDS.VizieR/J/ApJ/368/54
Title:
Velocities and Photometry for E and S0 galaxies
Short Name:
J/ApJ/368/54
Date:
21 Oct 2021
Publisher:
CDS
Description:
(Abstract from the paper) New spectroscopy and photometry have been obtained for 136 elliptical and S0 galaxies in the direction of the large-scale streaming flow attributed to the great attractor. Measurements of central velocity dispersion (sigma), total B magnitudes (B_T), the photometric parameter D_n, and the absorption-line index Mgi_2 are presented. Both internal and external comparisons indicate that measurements of log{sigma} are accurate to 0.05 dex, B_T to 0.15 mag, D_n to 0.015 dex, and Mg_2 to 0.017 mag. These data have been used in a previous paper by Dressler and Faber to estimate distances for these galaxies via the D_n - {sigma} relation. It is shown in this paper that the D_n - Mg_2 relation also predicts the same trends of peculiar velocity with distance, but with less accuracy. The relative accuracy of other distance indicators for elliptical galaxies is also discussed.
4493. Velocities and photometry in NGC 2112
ID:
ivo://CDS.VizieR/J/MNRAS/386/1625
Title:
Velocities and photometry in NGC 2112
Short Name:
J/MNRAS/386/1625
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report on a new, wide-field (20x20arcmin^2^), multicolour (UBVI), photometric campaign in the area of the nearby old open cluster NGC 2112. At the same time, we provide medium-resolution spectroscopy of 35 (and high-resolution of additional 5) red giant and turn-off stars. This material is analysed with the aim to update the fundamental parameters of this traditionally difficult cluster, which is very sparse and suffers from heavy field star contamination. Among the 40 stars with spectra, we identified 21 bona fide radial velocity members which allow us to put more solid constraints on the cluster's metal abundance, long suggested to be as low as the metallicity of globulars. As indicated earlier by us on a purely photometric basis, the cluster [Fe/H] abundance is slightly supersolar ([Fe/H]=0.16+/-0.03) and close to the Hyades value, as inferred from a detailed abundance analysis of three of the five stars with higher resolution spectra. Abundance ratios are also marginally supersolar. Based on this result, we revise the properties of NGC 2112 using stellar models from the Padova and Yale-Yonsei groups.
4494. Velocities and photometry in Trumpler 20
ID:
ivo://CDS.VizieR/J/A+A/561/A94
Title:
Velocities and photometry in Trumpler 20
Short Name:
J/A+A/561/A94
Date:
21 Oct 2021
Publisher:
CDS
Description:
Trumpler 20 is an old open cluster (OC) located toward the Galactic centre, at about 3kpc from the Sun and ~7kpc from the Galactic centre. Its position makes this cluster particularly interesting in the framework of the chemical properties of the Galactic disc because very few old OCs reside in the inner part of the disc. For this reason it has been selected as a cluster target of the Gaia-ESO Survey, and spectra of many stars in the main sequence and red clump phases are now available. Moreover, although it has been studied by several authors in the past, no consensus on the evolutionary status of Tr 20 has been reached. The heavy contamination of field stars (the line of sight of Tr 20 crosses the Carina spiral arm) complicates the correct interpretation. Another interesting aspect of the cluster is that it shows a broadened main sequence turn-off and a prominent and extended red clump, characteristics that are not easily explained by classical evolutionary models. Exploiting both spectroscopic information from the Gaia-ESO Survey (and the ESO archive) and literature photometry, we obtain a detailed and accurate analysis of the properties of the cluster. We make use of the first accurate metallicity measurement ever obtained from several spectra of red clump stars, and of cluster membership determination using radial velocities. According to the evolutionary models adopted, we find that Tr 20 has an age in the range 1.35-1.66Gyr, an average reddening E(B-V) in the range 0.31-0.35mag, a distance modulus (m-M)_0_ between 12.64 and 12.72mag. The spectroscopic metallicity is [Fe/H]=+0.17dex. We discuss the structural properties of the object and constrain possible hypotheses for its broadened upper main sequence, by estimating the effect of differential reddening, and its extended red clump.
4495. Velocities and transit times in the Kepler-88 system
ID:
ivo://CDS.VizieR/J/AJ/159/242
Title:
Velocities and transit times in the Kepler-88 system
Short Name:
J/AJ/159/242
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the discovery of Kepler-88d (P_d_=1403{+/-}14days, Msin_i_d__=965{+/-}44M_{Earth}_=3.04{+/-}0.13M_J_, e_d_=0.41{+/-}0.03) based on six years of radial velocity (RV) follow-up from the W.M.Keck Observatory High Resolution Echelle Spectrometer spectrograph. Kepler-88 has two previously identified planets. Kepler-88b (KOI-142.01) transits in the NASA Kepler photometry and has very large transit timing variations (TTVs). Nesvorny+, performed a dynamical analysis of the TTVs to uniquely identify the orbital period and mass of the perturbing planet (Kepler-88c), which was later was confirmed with RVs from the Observatoire de Haute-Provence (OHP). To fully explore the architecture of this system, we performed photodynamical modeling on the Kepler photometry combined with the RVs from Keck and OHP and stellar parameters from spectroscopy and Gaia. Planet d is not detectable in the photometry, and long-baseline RVs are needed to ascertain its presence. A photodynamical model simultaneously optimized to fit the RVs and Kepler photometry yields the most precise planet masses and orbital properties yet for b and c: P_b_=10.91647{+/-}0.00014days, M_b_=9.5{+/-}1.2M_{Earth}_, P_c_=22.2649{+/-}0.0007days, and M_c=214.0{+/-}5.3M_{Earth}_. The photodynamical solution also finds that planets b and c have low eccentricites and low mutual inclination, are apsidally anti-aligned, and have conjunctions on the same hemisphere of the star. Continued RV follow-up of systems with small planets will improve our understanding of the link between inner planetary system architectures and giant planets.
4496. Velocities and Washington photometry in Carina dSph
ID:
ivo://CDS.VizieR/J/ApJ/649/201
Title:
Velocities and Washington photometry in Carina dSph
Short Name:
J/ApJ/649/201
Date:
21 Oct 2021
Publisher:
CDS
Description:
A new large-area Washington M, T2+DDO51 filter survey of more than 10deg^2^ around the Carina dSph galaxy reveals a spectroscopically confirmed power-law radial density break population of Carina giant stars extending several degrees beyond the central King profile. Magellan telescope MIKE spectroscopy establishes the existence of Carina stars to at least 4.5 times its central King limiting radius, rlim, and primarily along Carina's major axis. To keep these stars bound to the dSph would require a global Carina mass-to-light ratio of M/L>=6300(M/L)_{sun}}. The MIKE velocities, supplemented with ~950 additional Carina field velocities from archived VLT+GIRAFFE spectra with r<~rlim, demonstrate a nearly constant Carina velocity dispersion (sigma_v_) to just beyond r=rlim and both a rising and a velocity shear at still larger radii. Together, the observational evidence suggests that the discovered extended Carina population represents tidal debris from the dSph.
4497. Velocities in NGC 4449
ID:
ivo://CDS.VizieR/J/AJ/124/3157
Title:
Velocities in NGC 4449
Short Name:
J/AJ/124/3157
Date:
21 Oct 2021
Publisher:
CDS
Description:
A detailed kinematic analysis of ionized gas in the nearby irregular galaxy NGC 4449 is presented. Observations were conducted in the spectral lines of H{alpha} and [S II]. Our scanning Fabry-Perot interferometric observations are presented from both a global and a local perspective. We have analyzed the global velocity field, the spatially extended diffuse gaseous component, and the H II region populations and, furthermore, have determined the rotation curve based on the heliocentric radial velocities of the global H{alpha} spatial distribution.
4498. Velocities in Pisces-Perseus supercluster.
ID:
ivo://CDS.VizieR/J/AJ/105/1251
Title:
Velocities in Pisces-Perseus supercluster.
Short Name:
J/AJ/105/1251
Date:
21 Oct 2021
Publisher:
CDS
Description:
Measurements of 544 radial velocities, 229 optical and 315 in the 21cm HI line, are presented for galaxies, mostly in the declination strip +33.5 deg<Dec<+39.5deg in the region of the Pisces-Perseus supercluster. These are combined with other available data to investigate the linear structure identified as the main supercluster ridge. The main ridge of the supercluster extends at least 50h^-1Mpc before it disappears into the zone of avoidance east of Perseus. Confinement both on the plane of the sky and in the velocity dimension imply an axial ratio of greater than ten to one and an inclination with respect to the plane of the sky of less than about 12 degrees. The smoothed volume density contrast over the whole ridge averages more than a factor of 6 relative to the average density derived for the whole sample. The relative proximity, low inclination to the plane of the sky, and high contrast relative to the foreground and background, help to make the Pisces-Perseus filament one of the most prominent features in the extragalactic sky on large scales.
4499. Velocities in the A2345 cluster
ID:
ivo://CDS.VizieR/J/A+A/521/A78
Title:
Velocities in the A2345 cluster
Short Name:
J/A+A/521/A78
Date:
21 Oct 2021
Publisher:
CDS
Description:
The connection of cluster mergers with the presence of extended, diffuse radio sources in galaxy clusters is still debated. We aim to obtain new insights into the internal dynamics of the cluster Abell 2345. This cluster exhibits two non-symmetric radio relics well studied through recent, deep radio data. Our analysis is based on redshift data for 125 galaxies acquired at the Telescopio Nazionale Galileo and on new photometric data acquired at the Isaac Newton Telescope. We also use ROSAT/HRI archival X-ray data. We combine galaxy velocities and positions to select 98 cluster galaxies and analyze the internal dynamics of the cluster.
4500. Velocities of Abell 610, 725 and 796 members
ID:
ivo://CDS.VizieR/J/A+A/487/33
Title:
Velocities of Abell 610, 725 and 796 members
Short Name:
J/A+A/487/33
Date:
21 Oct 2021
Publisher:
CDS
Description:
We study the dynamical status of the poor, low X-ray luminous galaxy clusters Abell 610, Abell 725, and Abell 796 (at z=0.1, 0.09, and 0.16, respectively), containing diffuse radio sources (relic, relic, and possible halo, respectively). Our analysis is based on new spectroscopic data obtained at the William Herschel Telescope for 158 galaxies, new photometry obtained at the Isaac Newton Telescope with the addition of data recovered from the Data Release 5 of the Sloan Digital Sky Survey. We use statistical tools to select 57, 36, and 26 cluster members and to analyze the kinematics of cluster galaxies, as well as to study the 2D cluster structure.