- ID:
- ivo://CDS.VizieR/J/A+A/429/309
- Title:
- HR 1099 radial velocities
- Short Name:
- J/A+A/429/309
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We studied orbital period changes in the non-eclipsing close binary HR 1099, one of the most bright members of the RS CVn class of magnetically active binary systems. Intermediate-resolution optical spectroscopy and IUE archive spectra were used to build radial-velocity curves yielding epochs of superior conjunction with an accuracy of 0.01 days. The final database ranged from 1976 to 2002 and allowed us a better assessment of the amplitude of the orbital period variation and its timescale.
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Search Results
- ID:
- ivo://CDS.VizieR/J/A+A/631/A71
- Title:
- HRS galaxies Halpha kinematic survey
- Short Name:
- J/A+A/631/A71
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present new 2D high resolution Fabry-Perot spectroscopic observations of 152 star-forming galaxies which are part of the Herschel Reference Survey (HRS), a complete K-band selected, volume-limited sample of nearby galaxies, spanning a wide range in stellar mass and morphological type. Using improved data reduction techniques that provide adaptive binning based on Voronoi tessellation, using large field-of-view observations, we derive high spectral resolution (R>10,000) H{alpha} datacubes from which we compute H{alpha} maps and radial 2D velocity fields that are based on several thousand independent measurements. A robust method based on such fields allows us to accurately compute rotation curves and kinematical parameters, for which uncertainties are calculated using a method based on the power spectrum of the residual velocity fields. We check the consistency of the rotation curves by comparing our maximum rotational velocities to those derived from Hi data, and computing the i-band, NIR, stellar and baryonic Tully-Fisher relations. We use this set of kinematical data combined to those available at other frequencies to study for the first time the relation between the dynamical and the total baryonic mass (stars, atomic and molecular gas, metals and dust), and derive the baryonic and dynamical main sequence on a representative sample of the local universe.
- ID:
- ivo://CDS.VizieR/J/A+A/258/243
- Title:
- HRV of Abell 151 galaxies
- Short Name:
- J/A+A/258/243
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use a sample of 65 redshifts to study the kinematics and dynamics of the cluster Abell 151. Data on individual galaxies are presented, and the accuracy of the determined velocities are discussed as well as some properties of the cluster. The velocity data reveal a foreground group and a background population at the same redshifts as the closely projected cluster A 166.
- ID:
- ivo://CDS.VizieR/J/ApJ/738/186
- Title:
- HST and DEIMOS measurements of NGC 2419 stars
- Short Name:
- J/ApJ/738/186
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the analysis of a kinematic data set of stars in the globular cluster NGC 2419, taken with the DEep Imaging Multi-Object Spectrograph at the Keck II telescope. Combined with a reanalysis of deep Hubble Space Telescope and Subaru Telescope imaging data, which provide an accurate luminosity profile of the cluster, we investigate the validity of a large set of dynamical models of the system, which are checked for stability via N-body simulations.
- ID:
- ivo://CDS.VizieR/J/ApJ/827/89
- Title:
- HST imaging of Pisces A and B
- Short Name:
- J/ApJ/827/89
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present observations of the Pisces A and B galaxies with the Advanced Camera for Surveys on the Hubble Space Telescope. Photometry from these images clearly resolves a red giant branch (RGB) for both objects, demonstrating that they are nearby dwarf galaxies. We describe a Bayesian inferential approach to determining the distance to these galaxies using the magnitude of the tip of the RGB (TRGB), and then apply this approach to these galaxies. This reveals the distance to these galaxies as 5.64_-0.15_^+0.13^Mpc and 8.89_-0.85_^+0.75^Mpc for Pisces A and B, respectively, placing both within the Local Volume but not the Local Group (LG). We estimate the star formation histories of these galaxies, which suggests that they have recently undergone an increase in their star formation rates. Together these yield luminosities for Pisces A and B of M_V_=-11.57_-0.05_^+0.06^ and -12.9+/-0.2, respectively, and estimated stellar masses of log(M*/M_{sun})=7.0_-1.7_^+0.4^ and 7.5_-1.8_^+0.3^. We further show that these galaxies are likely at the boundary between nearby voids and higher-density filamentary structure. This suggests that they are entering a higher-density region from voids, where they would have experienced delayed evolution, consistent with their recent increased star formation rates. If this is indeed the case, they are useful for study as proxies of the galaxies that later evolved into typical LG satellite galaxies.
- ID:
- ivo://CDS.VizieR/J/ApJS/97/1
- Title:
- HST Quasar Absorption Line Key Project. X.
- Short Name:
- J/ApJS/97/1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Sensitive H I 21cm emission line spectra have been measured for the directions to 143 quasars and AGNs chosen from the observing lists for the HST Quasar Absorption Line Key Project. Narrow-band and wide-band data were obtained with the NRAO 43m radio telescope for each object. The narrow-band data have a velocity resolution of 1km/s, extend from -220 to +170km/s, and are corrected for stray 21cm radiation. The wide-band data have a resolution of 4km/s and extend from -1000 to +1000km/s. The data are important for the interpretation of ultraviolet absorption lines near zero redshift in Key Project spectra. Twenty-two percent of the quasars lie behind Galactic high-velocity H I clouds with |VLSR|>100km/s whose presence can increase the equivalent width of interstellar absorption lines significantly. This paper contains the emission spectra and measures of the H I velocities and column densities along the sight line to each quasar. We discuss how the measurements can be used to estimate the visual and ultraviolet extinction toward each quasar and to predict the approximate strength of the strong ultraviolet resonance lines of neutral gas species in the HST Key Project spectra.
- ID:
- ivo://CDS.VizieR/J/A+A/532/A104
- Title:
- Hubble flow around Fornax cluster of galaxies
- Short Name:
- J/A+A/532/A104
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This work aims to provide a new mass estimate for the Fornax cluster and the Fornax-Eridanus complex, avoiding methods like the virial or fits of the X-ray emission profile, which assume that the system is in equilibrium. This is probably not the case for Fornax, because it is still in process of formation. Our mass estimate is based on determination of the zero-velocity surface, which, in the context of the spherical infall model, permits an evaluation of the total mass inside such a surface. The zero-velocity surface radius R0 was estimated either by a running median procedure or by fitting the data to the velocity field expected from the spherical model, including effects of the cosmological constant. The velocity field in a region within 20Mpc of the Fornax center was mapped using a list of 109 galaxies whose distances have an average accuracy of 0.31mag in their distance modulus. Our analysis indicates that the mass of the Fornax cluster itself is [0.40-3.32]x10^14^M_{sun}_ inside a radius of [2.62-5.18]Mpc while the mass inside [3.88-5.60]Mpc, corresponding to the Fornax-Eridanus complex, is [1.30-3.93]x10^14^M_{sun}_.
- ID:
- ivo://CDS.VizieR/J/A+A/592/A117
- Title:
- HU Vir radial velocities and VI light curves
- Short Name:
- J/A+A/592/A117
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigate the differential surface rotation on the primary star of the RS CVn binary HU Vir by tracking its starspot distribution as a function of time. We also recompute and update the values for several system parameters of the triple system HU Vir (close and wide orbits). Spectroscopic observations were carried out with the STELLA echelle spectrograph (SES) at the robotic 1.2-m STELLA-I telescope at the Observatorio del Teide in Tenerife, Spain. A time series of 118 echelle spectra was taken in the period between Feb 17 to Jun 26, 2013. Nine consecutive Doppler images were reconstructed from these data, using our line-profile inversion code iMap. An image cross-correlation method was applied to derive the surface differential-rotation law for HU Vir. New orbital elements for the close and the wide orbits were computed using our new STELLA RVs combined with the RV data available in the literature. Photometric observations were performed with the Amadeus Automatic Photoelectric Telescope (APT) at Fairborn Observatory in southern Arizona starting in 1996, providing contemporaneous Johnson-Cousins V and I data for approximately 20 years. This data was used to determine the stellar rotation period and the active longitudes.
709. Hyades membership
- ID:
- ivo://CDS.VizieR/J/A+A/331/81
- Title:
- Hyades membership
- Short Name:
- J/A+A/331/81
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use absolute trigonometric parallaxes from the Hipparcos Catalogue (Cat. <I/239>) to determine individual distances to members of the Hyades cluster, from which the 3-dimensional structure of the cluster can be derived. Inertially-referenced proper motions are used to rediscuss distance determinations based on convergent-point analyses. A combination of parallaxes and proper motions from Hipparcos, and radial velocities from ground-based observations, are used to determine the position and velocity components of candidate members with respect to the cluster centre, providing new information on cluster membership: 13 new candidate members within 20pc of the cluster centre have been identified. Farther from the cluster centre there is a gradual merging between certain cluster members and field stars, both spatially and kinematically. Within the cluster, the kinematical structure is fully consistent with parallel space motion of the component stars with an internal velocity dispersion of about 0.3km/s. The spatial structure and mass segregation are consistent with N-body simulation results, without the need to invoke expansion, contraction, rotation, or other significant perturbations of the cluster. The quality of the individual distance determinations permits the cluster zero-age main sequence to be accurately modelled. The helium abundance for the cluster is determined to be Y=0.26+/-0.02 which, combined with isochrone modelling including convective overshooting, yields a cluster age of 625+/-50Myr. The distance to the observed centre of mass (a concept meaningful only in the restricted context of the cluster members contained in the Hipparcos Catalogue) is 46.34+/-0.27pc, corresponding to a distance modulus m-M=3.33+/-0.01mag for the objects within 10pc of the cluster centre (roughly corresponding to the tidal radius). This distance modulus is close to, but significantly better determined than, that derived from recent high-precision radial velocity studies, somewhat larger than that indicated by recent ground-based trigonometric parallax determinations, and smaller than those found from recent studies of the cluster convergent point. These discrepancies are investigated and explained.
- ID:
- ivo://CDS.VizieR/J/A+A/486/697
- Title:
- Hydra I Cluster Catalogue (HCC)
- Short Name:
- J/A+A/486/697
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We analyse the properties of the early-type dwarf galaxy population in the Hydra I cluster. We investigate the galaxy luminosity function, the colour-magnitude relation, and the magnitude-surface brightness relation down to M_V_=-10mag. Deep VLT/FORS1 images in V and I bands were examined. We identify cluster members by radial velocity measurements and select other cluster galaxy candidates by their morphology. The candidates' total magnitudes and central surface brightnesses were derived from the analysis of their surface brightness profiles.
