- ID:
- ivo://CDS.VizieR/J/BaltA/10/481
- Title:
- HIP visual binaries kinematics. I.
- Short Name:
- J/BaltA/10/481
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A sample consisting of 570 binary systems is compiled from several sources of visual binary stars with well-known orbital elements. High-precision trigonometric parallaxes (mean relative error about 5%) and proper motions (mean relative error about 3%) are extracted from the Hipparcos Catalogue or from the reprocessed Hipparcos data. However, 13% of the sample stars lack radial velocity measurements. Computed galactic velocity components and other kinematic parameters are used to divide the sample stars into kinematic age groups. The majority (89%) of the sample stars, with known radial velocities, are the thin disk stars, 9.5% binaries have thick disk kinematics and only 1.4% are halo stars. 85% of thin disk binaries are young or medium age stars and almost 15% are old thin disk stars. There is an urgent need to increase the number of the identified halo binary stars with known orbits and substantially improve the situation with their radial velocity data. Based on the data from the Hipparcos astrometry satellite (ESA)
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Search Results
- ID:
- ivo://CDS.VizieR/J/BaltA/11/153
- Title:
- HIP visual binaries kinematics. II.
- Short Name:
- J/BaltA/11/153
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper continues kinematical investigation of the Hipparcos visual binaries with known orbits. A sample, consisting of 804 binary systems with orbital elements determined from ground-based observations, is selected. The mean relative error of their parallaxes is about 12% and the mean relative error of proper motions is about 4%. However, even 41% of the sample stars lack radial velocity measurements. The computed Galactic velocity components and other kinematical parameters are used to divide the stars with known radial velocities into kinematical age groups. The majority (92%) of binaries from the sample are thin disk stars, 7.6% have thick disk kinematics and only two binaries have halo kinematics. Among them, the long-period variable Mira Ceti has a very discordant Hipparcos and ground-based parallax values. From the whole sample, 60 stars are ascribed to the thick disk and halo population. There is an urgent need to increase the number of the identified halo binaries with known orbits and substantially improve the situation with radial velocity data for stars with known orbits. Based on the data from the Hipparcos astrometry satellite (ESA)
- ID:
- ivo://CDS.VizieR/J/AJ/127/3235
- Title:
- HIRES atlas of all RBGS galaxies
- Short Name:
- J/AJ/127/3235
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present high-resolution 12, 25, 60, and 100{mu}m images of 106 interacting galaxy systems contained in the IRAS Revised Bright Galaxy Sample (RBGS, Sanders et al., Cat. <J/AJ/126/1607>), a complete sample of all galaxies having a 60{mu}m flux density greater than 5.24Jy. These systems were selected to have at least two distinguishable galaxies separated by less than three average galactic diameters, and thus we have excluded very widely separated systems and very advanced mergers. Additionally, some systems have been included that are more than three galactic diameters apart, yet have separations less than 4 and are thus likely to suffer from confusion in the RBGS. The new complete survey has the same properties as the prototype survey of Surace et al., 1993AJ....105..864S.
- ID:
- ivo://CDS.VizieR/J/AJ/159/197
- Title:
- HIRES radial velocities of HD9446, HD43691 & HD179079
- Short Name:
- J/AJ/159/197
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Transit Ephemeris Refinement and Monitoring Survey is a project that aims to detect transits of intermediate-long period planets by refining orbital parameters of the known radial velocity planets using additional data from ground-based telescopes, calculating a revised transit ephemeris for the planet, then monitoring the planet host star during the predicted transit window. Here we present the results from three systems that had high probabilities of transiting planets: HD9446b and c, HD43691b, and HD179079b. We provide new radial velocity (RV) measurements that are then used to improve the orbital solution for the known planets. We search the RV data for indications of additional planets in orbit and find that HD9446 shows a strong linear trend of 4.8{sigma}. Using the newly refined planet orbital solutions, which include a new best-fit solution for the orbital period of HD9446c, and an improved transit ephemerides, we found no evidence of transiting planets in the photometry for each system. Transits of HD9446b can be ruled out completely and transits HD9446c and HD43691b can be ruled out for impact parameters up to b=0.5778 and b=0.898, respectively, due to gaps in the photometry. A transit of HD179079b cannot be ruled out, however, due to the relatively small size of this planet compared to the large star and thus low signal to noise. We determine properties of the three host stars through spectroscopic analysis and find through photometric analysis that HD9446 exhibits periodic variability.
- ID:
- ivo://CDS.VizieR/J/ApJ/785/126
- Title:
- HIRES radial velocity measurements
- Short Name:
- J/ApJ/785/126
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this paper we search for distant massive companions to known transiting gas giant planets that may have influenced the dynamical evolution of these systems. We present new radial velocity observations for a sample of 51 planets obtained using the Keck HIRES instrument, and find statistically significant accelerations in fifteen systems. Six of these systems have no previously reported accelerations in the published literature: HAT-P-10, HAT-P-22, HAT-P-29, HAT-P-32, WASP-10, and XO-2. We combine our radial velocity fits with Keck NIRC2 adaptive optics (AO) imaging data to place constraints on the allowed masses and orbital periods of the companions responsible for the detected accelerations. The estimated masses of the companions range between 1-500 M_Jup_, with orbital semi-major axes typically between 1-75 AU. A significant majority of the companions detected by our survey are constrained to have minimum masses comparable to or larger than those of the transiting planets in these systems, making them candidates for influencing the orbital evolution of the inner gas giant. We estimate a total occurrence rate of 51%+/-10% for companions with masses between 1-13 M_Jup_ and orbital semi-major axes between 1-20 AU in our sample. We find no statistically significant difference between the frequency of companions to transiting planets with misaligned or eccentric orbits and those with well-aligned, circular orbits. We combine our expanded sample of radial velocity measurements with constraints from transit and secondary eclipse observations to provide improved measurements of the physical and orbital characteristics of all of the planets included in our survey.
- ID:
- ivo://CDS.VizieR/J/AJ/139/315
- Title:
- HI-selected galaxies in SDSS. Optical data
- Short Name:
- J/AJ/139/315
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the optical data for 195 HI-selected galaxies that fall within both the Sloan Digital Sky Survey (SDSS) and the Parkes Equatorial Survey (ES). The photometric quantities have been independently recomputed for our sample using a new photometric pipeline optimized for large galaxies, thus correcting for SDSS's limited reliability for automatic photometry of angularly large or low surface brightness (LSB) galaxies.
- ID:
- ivo://CDS.VizieR/J/AJ/124/690
- Title:
- H I-selected galaxies in South Celestial Cap
- Short Name:
- J/AJ/124/690
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The first deep catalog of the H I Parkes All Sky Survey (HIPASS) is presented, covering the south celestial cap (SCC) region. The SCC area is ~2400deg^2^ and covers {delta}<-62{deg}. The average rms noise for the survey is 13 mJy/beam. Five hundred thirty-six galaxies have been catalogued according to their neutral hydrogen content, including 114 galaxies that have no previous catalogued optical counterpart. This is the largest sample of galaxies from a blind H I survey to date. Most galaxies in optically unobscured regions of sky have a visible optical counterpart; however, there is a small population of low-velocity H I clouds without visible optical counterparts whose origins and significance are unclear. The rms accuracy of the HIPASS positions is found to be 1.9'. The H I mass range of galaxies detected is from ~10^6^ to ~10^11^M_{sun}_.
- ID:
- ivo://CDS.VizieR/J/ApJ/833/270
- Title:
- HI-selected-Lyman limit system metallicities
- Short Name:
- J/ApJ/833/270
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We measured metallicities for 33 z=3.4-4.2 absorption line systems drawn from a sample of HI-selected-Lyman limit systems (LLSs) identified in Sloan Digital Sky Survey (SDSS) quasar spectra and stratified based on metal line features. We obtained higher-resolution spectra with the Keck Echellette Spectrograph and Imager, selecting targets according to our stratification scheme in an effort to fully sample the LLS population metallicity distribution. We established a plausible range of HI column densities and measured column densities (or limits) for ions of carbon, silicon, and aluminum, finding ionization-corrected metallicities or upper limits. Interestingly, our ionization models were better constrained with enhanced {alpha}-to-aluminum abundances, with a median abundance ratio of [{alpha}/Al]=0.3. Measured metallicities were generally low, ranging from [M/H]=-3 to -1.68, with even lower metallicities likely for some systems with upper limits. Using survival statistics to incorporate limits, we constructed the cumulative distribution function (CDF) for LLS metallicities. Recent models of galaxy evolution propose that galaxies replenish their gas from the low-metallicity intergalactic medium (IGM) via high-density HI "flows" and eject enriched interstellar gas via outflows. Thus, there has been some expectation that LLSs at the peak of cosmic star formation (z~3) might have a bimodal metallicity distribution. We modeled our CDF as a mix of two Gaussian distributions, one reflecting the metallicity of the IGM and the other representative of the interstellar medium of star-forming galaxies. This bimodal distribution yielded a poor fit. A single Gaussian distribution better represented the sample with a low mean metallicity of [M/H]~-2.5.
- ID:
- ivo://CDS.VizieR/J/ApJ/833/283
- Title:
- HI-selected Lyman limit systems metallicities
- Short Name:
- J/ApJ/833/283
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first results from our KODIAQ Z survey aimed at determining the metallicity distribution and physical properties of the z>~2 partial and full Lyman limit systems (pLLSs and LLSs; 16.2<=logN_HI_<19), which are probed of the interface regions between the intergalactic medium (IGM) and galaxies. We study 31 HI-selected pLLSs and LLSs at 2.3<z<3.3 observed with Keck/HIRES in absorption against background QSOs. We compare the column densities of metal ions to HI and use photoionization models to assess the metallicity. The metallicity distribution of the pLLSs/LLSs at 2.3<z<3.3 is consistent with a unimodal distribution peaking at [X/H]~-2. The metallicity distribution of these absorbers therefore evolves markedly with z since at z<~1 it is bimodal with peaks at [X/H]~-1.8 and -0.3. There is a substantial fraction (25%-41%) of pLLSs/LLSs with metallicities well below those of damped Ly{alpha} absorbers (DLAs) at any studied z from z<~1 to z~2-4, implying reservoirs of metal-poor, cool, dense gas in the IGM/galaxy interface at all z. However, the gas probed by pLLSs and LLSs is rarely pristine, with a fraction of 3%-18% for pLLSs/LLSs with [X/H]<=-3. We find C/{alpha} enhancement in several pLLSs and LLSs in the metallicity range -2<~[X/H]<~-0.5, where C/{alpha} is 2-5 times larger than observed in Galactic metal-poor stars or high-redshift DLAs at similar metallicities. This is likely caused by preferential ejection of carbon from metal-poor galaxies into their surroundings.
- ID:
- ivo://CDS.VizieR/J/ApJ/626/195
- Title:
- HI self-absorption (HISA) survey in the CGPS
- Short Name:
- J/ApJ/626/195
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a 21cm line HI self-absorption (HISA) survey of cold atomic gas within Galactic longitudes l=75{deg} to 146{deg} and latitudes b=-3{deg} to +5{deg}. We identify HISA as spatially and spectrally confined dark HI features and extract it from the surrounding HI emission in the arcminute-resolution Canadian Galactic Plane Survey (CGPS). We compile a catalog of the most significant features in our survey and compare our detections against those in the literature. Within the parameters of our search, we find nearly all previously detected features and identify many new ones.