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- ID:
- ivo://CDS.VizieR/J/AJ/151/106
- Title:
- Radial velocities in 2006-2014 for HD 89758
- Short Name:
- J/AJ/151/106
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report that the spectroscopic binary {mu} Ursae Majoris ({mu} UMa) has secondary RV variations of 471.2 days in addition to those of 230.0 days already known. Keplerian orbit analysis yields stellar mass companions of 1.6M_{sun}_ for the 230 day period and 0.14M_{sun}_for the 471 day period. However, the HIPPARCOS photometries show a period similar to the stellar rotational period, which is one-quarter of the RV period. Variations in the bisector velocity curvature show a period of 463.6 days. We also find ~473 day variations in the equivalent width (EW) measurements of the H_{alpha}_ and H_{beta}_ lines, whose origin is probably stellar activity. We note that the nature of 471 day variations is similar to one observed in "Sequence D" of Asymptotic Giant Branch pulsating stars. We therefore conclude that the RV and the EW variations in the spectroscopic binary M giant {mu} UMa A originate from the complex pulsations and the chromospheric activity.
- ID:
- ivo://CDS.VizieR/J/AJ/131/2114
- Title:
- Radial velocities in Fornax dSph
- Short Name:
- J/AJ/131/2114
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present new radial velocity results for 176 stars in the Fornax dwarf spheroidal galaxy, of which at least 156 are probable Fornax members. We combine with previously published data to obtain a radial velocity sample with 206 stars, of which at least 176 are probable Fornax members.
- ID:
- ivo://CDS.VizieR/J/AJ/162/66
- Title:
- Radial Velocities in HD50526 system with CORALIE
- Short Name:
- J/AJ/162/66
- Date:
- 14 Mar 2022 08:24:15
- Publisher:
- CDS
- Description:
- We present a photometric and spectroscopic study of HD50526, an ellipsoidal binary member of the group Double Periodic Variable stars. Performing data mining in photometric surveys and conducting new spectroscopic observations with several spectrographs during 2008-2015, we obtained orbital and stellar parameters of the system. The radial velocities were analyzed with the genetic PIKAIA algorithm, whereas Doppler tomography maps for the H{alpha} and H{beta} lines were constructed with the Total Variation Minimization code. An optimized simplex algorithm was used to solve the inverse problem adjusting the light curve with the best stellar parameters for the system. We find an orbital period of 6.701{+/-}0.001d and a long photometric cycle of 191{+/-}2 days. We detected the spectral features of the coldest star and modeled it with a logg=2.79{+/-}0.02dex giant of mass 1.13{+/-}0.02 M{sun} and effective temperature 10500{+/-}125K. In addition, we determine a mass ratio q=0.206{+/-}0.033 and that the hot star is a B-type dwarf of mass 5.48{+/-}0.02M{sun}. The V-band orbital light curve can be modeled including the presence of an accretion disk around the hotter star. This fills the Roche lobe of the hotter star and has a radius 14.74{+/-}0.02R{sun} and the temperature at the outer edge is 9400 K. Two bright spots located in the disk account for the global morphology of the light curve. The Doppler tomography maps of H{alpha} and H{beta} reveal complex structures of mass fluxes in the system.
- ID:
- ivo://CDS.VizieR/J/A+A/386/187
- Title:
- Radial velocities in IC 4651
- Short Name:
- J/A+A/386/187
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The radial-velocity observations were made during the years 1989-1997 with the photoelectric scanner CORAVEL (Mayor, 1985IAUCo..88...35M) on the Danish 1.54-m telescope at ESO, La Silla. The individual mean errors given are computed from the measured S/N ratio and the shape of the cross-correlation profile (see Sect. 2.2 of this paper).
- ID:
- ivo://CDS.VizieR/J/AJ/150/97
- Title:
- Radial velocities in M67. I. 1278 candidate members
- Short Name:
- J/AJ/150/97
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present results from 13776 radial-velocity (RV) measurements of 1278 candidate members of the old (4Gyr) open cluster M67 (NGC 2682). The measurements are the results of a long-term survey that includes data from seven telescopes with observations for some stars spanning over 40years. For narrow-lined stars, RVs are measured with precisions ranging from about 0.1 to 0.8km/s. The combined stellar sample reaches from the brightest giants in the cluster down to about 4mag below the main-sequence turnoff (V=16.5), covering a mass range of about 1.34M_{sun}_ to 0.76M_{sun}_. Spatially, the sample extends to a radius of 30arcmin (7.4pc in projection at a distance of 850pc or 6-7 core radii). We find M67 to have a mean radial velocity of +33.64km/s (with an internal precision of +/-0.03km/s) well separated from the mean velocity of the field. For stars with >=3 measurements, we derive RV membership probabilities and identify RV variables, finding 562 cluster members, 142 of which show significant RV variability. We use these cluster members to construct a color-magnitude diagram and identify a rich sample of stars that lie far from the standard single star isochrone, including the well-known blue stragglers, sub-subgiants and yellow giants. These exotic stars have a binary frequency of (at least) 80%, more than three times that detected for stars in the remainder of the sample. We confirm that the cluster is mass segregated, finding the binaries to be more centrally concentrated than the single stars in our sample at the 99.8% confidence level (and at the 98.7% confidence level when only considering main-sequence stars). The blue stragglers are centrally concentrated as compared to the solar-type main-sequence single stars in the cluster at the 99.7% confidence level. Accounting for measurement precision, we derive an RV dispersion in M67 of 0.80+/-0.04km/s for our sample of single main-sequence stars, subgiants and giants with V{<=}15.5. When corrected for undetected binaries, this sample yields a true RV dispersion of 0.59_-0.06_^+0.07^km/s. The radial distribution of the velocity dispersion is consistent with an isothermal distribution within our stellar sample. Using the cluster RV dispersion, we estimate a virial mass for the cluster of 2100_-550_^+610^M_{sun}_.
- ID:
- ivo://CDS.VizieR/J/A+A/566/A58
- Title:
- Radial velocities in M3, M13, and M92
- Short Name:
- J/A+A/566/A58
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Radial velocity data are presented for three Galactic globular clusters, M3, M13, and M92. The provided catalogues include several hundreds of stars in each cluster that cover a wide range of distances to the cluster centres. Besides the measured radial velocities, the catalogues contain measurement uncertainties, identifiers, world coordinates and variability information for each star. The velocities for stars near the centres of the clusters were obtained using PMAS integral field spectroscopy (IFS). Note that in order to facilitate future variability studies, for each star the individual velocity measurements are provided instead of a single combined velocity. The PMAS data are complemented with velocities reported in various literature studies for stars at larger distances to the centres.
- ID:
- ivo://CDS.VizieR/J/AJ/139/1383
- Title:
- Radial velocities in M35 (NGC 2168)
- Short Name:
- J/AJ/139/1383
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present 5201 radial-velocity (RV) measurements of 1144 stars as part of an ongoing study of the young (150Myr) open cluster M35 (NGC 2168). We have observed M35 since 1997, using the Hydra Multi-Object Spectrograph on the WIYN 3.5m telescope.
- ID:
- ivo://CDS.VizieR/J/A+A/462/L9
- Title:
- Radial velocities in NGC 7099
- Short Name:
- J/A+A/462/L9
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A test of Newton's law of gravity in the low acceleration regime using globular clusters is presented and new results for the core collapsed globular cluster NGC 7099 given. The run of the gravitational potential as a function of distance is probed by studying the velocity dispersion profile of the cluster, as derived from a set of 125 radial velocities with accuracy better than 1km/s. The velocity dispersion profile is traced up to ~18pc from the cluster center. The dispersion is found to be maximal at the center, then decrease until 10+/-2pc from the center, well inside the cluster tidal radius of 42pc. After that the dispersion remains basically constant with an average value of 2.2+/-0.3km/s. Assuming a total V magnitude of M(V)=-7.43mag for NGC 7099, the acceleration at 10+/-2pc from the center is 1.1^+0.4_-0.3_{tau}x10^-8^cm/s^2^, where {tau} is the mass-to-light ratio. Thus, for {tau}>~2 typical of globular clusters, the flattening of the velocity dispersion profile occurs for a value of the internal acceleration of gravity that is fully consistent with a_0_=1.2x10^-8^cm/s^2^ observed in galaxies. This new result for NGC 7099 brings to 4 the clusters with velocity dispersion profile probing acceleration below a_0_. All four have been found to have a flat dispersion profile at large radii where the acceleration is below a_0_, thereby mimicking elliptical galaxies qualitatively and quantitatively. Whether this indicates a failure of Newtonian dynamics in the low acceleration limit or some more conventional dynamical effect (e.g., tidal heating) is still unclear. However, the similarities emerging between very different globular clusters, as well as between globular clusters and elliptical galaxies, seem to favor the first of these two possibilities.
- ID:
- ivo://CDS.VizieR/J/MNRAS/426/1137
- Title:
- Radial velocities in NGC 1851
- Short Name:
- J/MNRAS/426/1137
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the result of a spectroscopic survey performed in the outskirts of the globular cluster NGC1851 with Visible MultiObject Spectrograph (VIMOS)/Very Large Telescope (VLT) with the medium-resolution grism coupled with the GG475 filter. The spectral coverage is from 5000 to 8000{AA} with a resolution R~580. Target stars have been selected from the photometry of Carballo-Bello et al. (2012MNRAS.419...14C), sampling a wide range in magnitude and colour (16<B<22, 0.6<B-R<2.1). We report the radial velocities of 107 stars in a region between 12 and 33 arcmin around the cluster centre. Observations have been performed during three nights in 2008 October at the Very Large Telescope's (VLT) Unit Telescope 3 (Melipal) at the European Southern Observatory (ESO), Cerro Paranal, Chile, equipped with the VIsible MultiObject Spectrograph (VIMOS). Velocities have been obtained by cross-correlating the spectra of the individual exposures with a GIRAFFE solar spectrum smoothed to the resolution of our targets using the region of the H-alpha line. Typical errors are of about 15km/s.
