- 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.
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- 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.
- 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.
4474. 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.
- 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.
- 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.
- 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.
- ID:
- ivo://CDS.VizieR/J/ApJ/588/824
- Title:
- Velocities of blue stars near (l,b)=(198,-27)
- Short Name:
- J/ApJ/588/824
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present evidence for a ring of stars in the plane of the Milky Way, extending at least from l=180{deg} to 227{deg} with turnoff magnitude g~19.5; the ring could encircle the Galaxy. We infer that the low Galactic latitude structure is at a fairly constant distance of R=18+/-2kpc from the Galactic center above the Galactic plane and has R=20+/-2kpc in the region sampled below the Galactic plane. The evidence includes 500 Sloan Digital Sky Survey spectroscopic radial velocities of stars within 30{deg} of the plane. The velocity dispersion of the stars associated with this structure is found to be 27km/s at (l, b)=(198, -27), 22km/s at (l, b)=(225, 28), 30km/s at (l, b)=(188, 24), and 30km/s at (l, b)=(182, 27). The structure rotates in the same prograde direction as the Galactic disk stars but with a circular velocity of 110+/-25km/s. The narrow measured velocity dispersion is inconsistent with power-law spheroid or thick-disk populations.
- ID:
- ivo://CDS.VizieR/J/A+A/485/95
- Title:
- Velocities of F-G-K stars in Blanco 1
- Short Name:
- J/A+A/485/95
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The nearby open cluster Blanco 1 is of considerable astrophysical interest for formation and evolution studies of open clusters because it is the third highest Galactic latitude cluster known. It has been observed often, but so far no definitive and comprehensive membership determination is readily available. An observing programme was carried out to study the stellar population of Blanco 1, and especially the membership and binary frequency of the F5-K0 dwarfs. We obtained radial-velocities with the CORAVEL spectrograph in the field of Blanco 1 for a sample of 148 F-G-K candidate stars in the magnitude range 10<V<14. New proper motions and UBVI CCD photometric data from two extensive surveys were obtained independently and are used to establish reliable cluster membership assignments in concert with radial-velocity data. The membership of 68 stars is confirmed on the basis of proper motion, radial velocity, and photometric criteria. Fourteen spectroscopic- and suspected binaries (2 SB2s, 9 SB1s, 3SB?) have been discovered among the confirmed members. Thirteen additional stars are located above the main sequence or close to the binary ridge, with radial velocities and proper motions supporting their membership. These are probable binaries with wide separations. Nine binaries (7 SB1 and 2 SB2) were detected among the field stars. The spectroscopic binary frequency among members is 20% (14/68); however, the overall binary rate reaches 40% (27/68) if one includes the photometric binaries. The cluster mean heliocentric radial velocity is +5.53+/-0.11km/s based on the most reliable 49 members. The Vsini distribution is similar to that of the Pleiades, confirming the age similarities between the two clusters.
- ID:
- ivo://CDS.VizieR/J/AJ/147/150
- Title:
- Velocities of globular clusters in M104
- Short Name:
- J/AJ/147/150
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have obtained radial velocity measurements for 51 new globular clusters around the Sombrero galaxy. These measurements were obtained using spectroscopic observations from the AAOmega spectrograph on the Anglo-Australian Telescope and the Hydra spectrograph at WIYN. Combining our own past measurements and velocity measurements obtained from the literature, we have constructed a large database of radial velocities that contains a total of 360 confirmed globular clusters. Previous studies' analyses of the kinematics and mass profile of the Sombrero globular cluster system have been constrained to the inner ~9' (~24kpc or ~5R_e_), but our new measurements have increased the radial coverage of the data, allowing us to determine the kinematic properties of M104 out to ~15' (~41kpc or ~9R_e_). We use our set of radial velocities to study the GC system kinematics and to determine the mass profile and V-band mass-to-light profile of the galaxy. We find that M/L_V_ increases from 4.5 at the center to a value of 20.9 at 41kpc (~9R_e_ or 15'), which implies that the dark matter halo extends to the edge of our available data set. We compare our mass profile at 20kpc (~4R_e_or ~7.4') to the mass computed from X-ray data and find good agreement. We also use our data to look for rotation in the globular cluster system as a whole, as well as in the red and blue subpopulations. We find no evidence for significant rotation in any of these samples.
