- ID:
- ivo://CDS.VizieR/J/A+AS/126/471
- Title:
- HI data of galaxies from Kazarian's lists
- Short Name:
- J/A+AS/126/471
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The 21-cm neutral hydrogen line has been measured for the first time in 39 non-Seyfert type galaxies from Kazarian list, with the Nancay radiotelescope. The line profiles, widths at 20% and 50% of the peak intensity, radial velocities as well as total fluxes are presented. The values of radial velocity are in fairly good agreement with those obtained from optical spectra. The width values at 20% of the peak vary in wide range from 113km/s (KAZ 579) to 608km/s for KAZ 566. Nine of our objects remained undetected, whether their HI-flux was too faint, the integration time too short, or the frequency sighted wrong. However, for part of them, there were positive hint of detection. Comments on individual objects are given.
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Search Results
442. HIDEEP survey
- ID:
- ivo://CDS.VizieR/J/MNRAS/346/787
- Title:
- HIDEEP survey
- Short Name:
- J/MNRAS/346/787
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have carried out an extremely long integration time (9000s/beam) 21-cm blind survey of 60deg^2^ in Centaurus using the Parkes multibeam system. We find that the noise continues to fall as sqrt(t_obs_) throughout, enabling us to reach an H I column-density limit of 4.2x10^18^cm^-2^ for galaxies with a velocity width of 200km/s in the central 32deg^2^ region, making this the deepest survey to date in terms of column density sensitivity. The H I data are complemented by very deep optical observations from digital stacking of multi-exposure UK Schmidt Telescope R-band films, which reach an isophotal level of 26.5Rmag/arcsec^2^ (27.5Bmag/arcsec^2^). 173 H I sources have been found, 96 of which have been uniquely identified with optical counterparts in the overlap area.
- ID:
- ivo://CDS.VizieR/J/MNRAS/468/1726
- Title:
- HIDES. II. Double- and triple-lined objects
- Short Name:
- J/MNRAS/468/1726
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of our spectroscopic observations of eight detached eclipsing binaries (DEBs), selected from the Kepler Eclipsing Binary Catalog. Radial velocities (RVs) were calculated from high-resolution spectra obtained with the HIgh-Dispersion Echelle Spectrograph (HIDES) spectrograph, attached to the 1.88-m telescope of the Okayama Astrophysical Observatory, and were used to characterize the targets in combination with the Kepler light curves. For each binary, we obtained a full set of orbital and physical parameters, reaching precision below 3 per cent in masses and radii for five pairs. By comparing our results with theoretical models, we assess the distance, age and evolutionary status of the researched objects. We also study eclipse timing variations of selected objects, and identify a new system with a {gamma} Dor pulsator. Two systems are triples, and show lines coming from three components. In one case, the motion of the outer star and the perturbation in the RVs of the inner binary are clearly visible and periodical, which allows us to directly calculate the mass of the third star and inclination of the outer orbit. In the second case, we only see a clear motion of the tertiary and investigate two scenarios: that it is a linear trend coming from the orbital motion around the inner binary and that it is caused by a planetary mass companion. When possible, we also compare our results with the literature, and conclude that only by combining photometry with RVs, it is possible to obtain correct physical parameters of both components of a DEB.
- ID:
- ivo://CDS.VizieR/J/MNRAS/461/2896
- Title:
- HIDES. I. Single-lined objects
- Short Name:
- J/MNRAS/461/2896
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present results of our spectroscopic observations of nine detached eclipsing binaries (DEBs), selected from the Kepler Eclipsing Binary Catalog, that only show one set of spectral lines. Radial velocities (RVs) were calculated from the high-resolution spectra obtained with the HIgh-Dispersion Echelle Spectrograph (HIDES) instrument, attached to the 1.88-m telescope at the Okayama Astrophysical Observatory, and from the public Apache Point Observatory Galactic Evolution Experiment archive. In our sample, we found five single-lined binaries, with one component dominating the spectrum. The orbital and light-curve solutions were found for four of them, and compared with isochrones, in order to estimate absolute physical parameters and evolutionary status of the components. For the fifth case, we only update the orbital parameters, and estimate the properties of the unseen star. Two other systems show orbital motion with a period known from the eclipse timing variations (ETVs). For these we obtained parameters of outer orbits, by translating the ETVs to RVs of the centre of mass of the eclipsing binary, and combining with the RVs of the outer star. Of the two remaining ones, one is most likely a blend of a faint background DEB with a bright foreground star, which lines we see in the spectra, and the last case is possibly a quadruple bearing a sub-stellar mass object. Where possible, we compare our results with literature, especially with results from asteroseismology. We also report possible detections of solar-like oscillations in our RVs.
- ID:
- ivo://CDS.VizieR/J/MNRAS/441/343
- Title:
- Highly eccentric detached eclipsing binaries
- Short Name:
- J/MNRAS/441/343
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Next-generation synoptic photometric surveys will yield unprecedented (for the astronomical community) volumes of data and the processes of discovery and rare-object identification are, by necessity, becoming more autonomous. Such autonomous searches can be used to find objects of interest applicable to a wide range of outstanding problems in astronomy, and in this paper we present the methods and results of a largely autonomous search for highly eccentric detached eclipsing binary systems in the Machine-learned All-Sky Automated Survey Classification Catalog. 106 detached eclipsing binaries with eccentricities of e>~0.1 are presented, most of which are identified here for the first time. We also present new radial-velocity curves and absolute parameters for six of those systems with the long-term goal of increasing the number of highly eccentric systems with orbital solutions, thereby facilitating further studies of the tidal circularization process in binary stars.
- ID:
- ivo://CDS.VizieR/J/AJ/156/179
- Title:
- Highly r-process-enhanced field stars kinematics
- Short Name:
- J/AJ/156/179
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the kinematics of 35 highly r-process-enhanced ([Eu/Fe]>=+0.7) metal-poor (-3.8<[Fe/H]< -1.4) field stars. We calculate six-dimensional positions and velocities, evaluate energies and integrals of motion, and compute orbits for each of these stars using parallaxes and proper motions from the second Gaia data release (Cat. I/345) and published radial velocities. All of these stars have halo kinematics. Most stars (66%) remain in the inner regions of the halo (<13 kpc), and many (51%) have orbits that pass within 2.6 kpc of the Galactic center. Several stars (20%) have orbits that extend beyond 20 kpc, including one with an orbital apocenter larger than the Milky Way virial radius. We apply three clustering methods to search for structure in phase space, and we identify eight groups. No abundances are considered in the clustering process, but the [Fe/H] dispersions of the groups are smaller than would be expected by random chance. The orbital properties, clustering in phase space and metallicity, and the lack of highly r-process-enhanced stars on disk-like orbits, indicate that such stars likely were accreted from disrupted satellites. Comparison with the galaxy luminosity-metallicity relation suggests M_V_>~-9 for most of the progenitor satellites, characteristic of ultra-faint or low-luminosity classical dwarf spheroidal galaxies. Environments with low rates of star formation and Fe production, rather than the nature of the r-process site, may be key to obtaining the [Eu/Fe] ratios found in highly r-process-enhanced stars.
- ID:
- ivo://CDS.VizieR/J/ApJ/719/1293
- Title:
- High precision orbits of 5 SB2 stars
- Short Name:
- J/ApJ/719/1293
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present high-precision radial velocities (RVs) of double-lined spectroscopic binary stars HD78418, HD123999, HD160922, HD200077, and HD210027. They were obtained based on the high-resolution echelle spectra collected with the Keck I/HIRES, Shane/CAT/Hamspec, and TNG/Sarge telescopes/spectrographs over the years 2003-2008 as part of the TATOOINE search for circumbinary planets. The RVs were computed using our novel iodine cell technique for double-line binary stars, which relies on tomographically disentangled spectra of the components of the binaries. The precision of the RVs is of the order of 1-10m/s, and to properly model such measurements one needs to account for the light-time effect within the binary's orbit, relativistic effects, and RV variations due to tidal distortions of the components of the binaries. With such proper modeling, our RVs combined with the archival visibility measurements from the Palomar Testbed Interferometer (PTI) allow us to derive very precise spectroscopic/astrometric orbital and physical parameters of the binaries.
- ID:
- ivo://CDS.VizieR/J/ApJ/898/150
- Title:
- High-res. MIKE obs. of metal-poor stars
- Short Name:
- J/ApJ/898/150
- Date:
- 21 Mar 2022 08:50:22
- Publisher:
- CDS
- Description:
- Extensive progress has recently been made in our understanding of heavy-element production via the r-process in the universe, specifically with the first observed neutron star binary merger (NSBM) event associated with the gravitational-wave signal detected by LIGO, GW170817. The chemical abundance patterns of metal-poor r-process-enhanced stars provide key evidence for the dominant site(s) of the r-process and whether NSBMs are sufficiently frequent or prolific r-process sources to be responsible for the majority of r-process material in the universe. We present atmospheric stellar parameters (using a nonlocal thermodynamic equilibrium analysis) and abundances from a detailed analysis of 141 metal-poor stars carried out as part of the R-Process Alliance (RPA) effort. We obtained high-resolution "snapshot" spectroscopy of the stars using the MIKE spectrograph on the 6.5m Magellan Clay telescope at Las Campanas Observatory in Chile. We find 10 new highly enhanced r-II (with [Eu/Fe]>+1.0), 62 new moderately enhanced r-I (+0.3<[Eu/Fe]<~+1.0), and 17 new limited-r ([Eu/Fe]<+0.3) stars. Among those, we find 17 new carbon-enhanced metal-poor (CEMP) stars, of which five are CEMP-no. We also identify one new s-process-enhanced ([Ba/Eu]>+0.5) and five new r/s (0.0<[Ba/Eu]<+0.5) stars. In the process, we discover a new ultra-metal-poor (UMP) star at [Fe/H]=-4.02. One of the r-II stars shows a deficit in {alpha} and Fe-peak elements, typical of dwarf galaxy stars. Our search for r-process-enhanced stars by RPA efforts has already roughly doubled the known r-process sample.
- ID:
- ivo://CDS.VizieR/J/ApJ/822/40
- Title:
- High resolution NIR RVs of K2-M4 low-mass stars
- Short Name:
- J/ApJ/822/40
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of a precise near-infrared (NIR) radial velocity (RV) survey of 32 low-mass stars with spectral types K2-M4 using CSHELL at the NASA InfraRed Telescope Facility in the K band with an isotopologue methane gas cell to achieve wavelength calibration and a novel, iterative RV extraction method. We surveyed 14 members of young (~25-150Myr) moving groups, the young field star {epsilon} Eridani, and 18 nearby (<25pc) low-mass stars and achieved typical single-measurement precisions of 8-15m/s with a long-term stability of 15-50m/s over longer baselines. We obtain the best NIR RV constraints to date on 27 targets in our sample, 19 of which were never followed by high-precision RV surveys. Our results indicate that very active stars can display long-term RV variations as low as ~25-50m/s at ~2.3125{mu}m, thus constraining the effect of jitter at these wavelengths. We provide the first multiwavelength confirmation of GJ876bc and independently retrieve orbital parameters consistent with previous studies. We recovered RV variabilities for HD160934AB and GJ725AB that are consistent with their known binary orbits, and nine other targets are candidate RV variables with a statistical significance of 3{sigma}-5{sigma}. Our method, combined with the new iSHELL spectrograph, will yield long-term RV precisions of <~5m/s in the NIR, which will allow the detection of super-Earths near the habitable zone of mid-M dwarfs.
- ID:
- ivo://CDS.VizieR/J/A+A/514/A97
- Title:
- High-resolution spectra of Late-type stars
- Short Name:
- J/A+A/514/A97
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- * Aims: We present a compilation of spectroscopic data from a survey of 144 chromospherically active young stars in the solar neighborhood which may be used to investigate different aspects of the formation and evolution of the solar neighborhood in terms of kinematics and stellar formation history. The data have already been used by us in several studies. With this paper, we make all these data accessible to the scientific community for future studies on different topics. * Methods: We performed spectroscopic observations with echelle spectrographs to cover the entirety of the optical spectral range simultaneously. Standard data reduction was performed with the IRAF echelle package. We applied the spectral subtraction technique to reveal chromospheric emission in the stars of the sample. The equivalent width of chromospheric emission lines was measured in the subtracted spectra and then converted to fluxes using equivalent width--flux relationships. Radial and rotational velocities were determined by the cross-correlation technique. Kinematics, equivalent widths of the lithium line 6707.8{AA} and spectral types were also determined. * Results: A catalog of spectroscopic data is compiled: radial and rotational velocities, space motion, equivalent widths of optical chromospheric activity indicators from Ca II H & K to the calcium infrared triplet and the lithium line in 6708{AA}. Fluxes in the chromospheric emission lines and R'_HK are also determined for each observation of star in the sample. We used these data to investigate the emission levels of our stars. The study of the H{alpha} emission line revealed the presence of two different populations of chromospheric emitters in the sample, clearly separated in the log(F_H{alpha}_/F_bol_)-(V-J) diagram. The dichotomy may be associated with the age of the stars.