- ID:
- ivo://CDS.VizieR/J/A+AS/140/79
- Title:
- Radii of 22 galactic Cepheids
- Short Name:
- J/A+AS/140/79
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present radial velocity data for 22 galactic Cepheid stars obtained with Coravel spectrometer. Continuous observation over several years has enabled us to obtain 852 individual velocities covering all the phases of the pulsation. The mean number of measurements per star is 39, ranging from 20 to 113. For each star radial velocity versus phase diagrams have been fitted by analytical relation, and the stellar radius variation has been derived by integration of this relation over the whole period. Using recent ubv photometry of the literature and velocity curves, we have calculated the radii of the stars using a method based on the Baade-Wesselink concept. For these 22 Cepheids we give a linear logarithmic period-radius relation with a range of 2,4 to 45 days.
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- ID:
- ivo://CDS.VizieR/J/ApJS/165/338
- Title:
- Radio recombination lines in HII regions
- Short Name:
- J/ApJS/165/338
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report radio recombination line (RRL) and continuum observations of a sample of 106 Galactic HII regions made with the NRAO 140 Foot (43m) radio telescope in Green Bank, West Virginia. We believe this to be the most sensitive RRL survey ever made for a sample this large. Most of our source integration times range between 6 and 90 hr, yielding typical rms noise levels of ~1.0-3.5mK. Our data result from two different experiments performed, calibrated, and analyzed in similar ways. A CII survey was made at the 3.5cm wavelength to obtain accurate measurements of carbon radio recombination lines. When combined with atomic (CI) and molecular (CO) data, these measurements will constrain the composition, structure, kinematics, and physical properties of the photodissociation regions that lie on the edges of HII regions. A second survey was made at the 3.5cm wavelength to determine the abundance of ^3^He in the interstellar medium of the Milky Way. Together with measurements of the ^3^He^+^ hyperfine line, we get high-precision RRL parameters for H, ^4^He, and C. Here we discuss significant improvements in these data with both longer integrations and newly observed sources.
- ID:
- ivo://CDS.VizieR/J/A+A/171/261
- Title:
- Radio Recombination Lines of Southern HII Regions
- Short Name:
- J/A+A/171/261
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We tabulate velocities and other parameters of hydrogen recombination lines near 5GHz (H109{alpha} and H110{alpha}) for 316 HII regions observed with the Parkes 64-m radio telescope. Results of a new search for formaldehyde absorption are also listed. Source selection was based on the 5GHz continuum southern galactic plane survey of Haynes et al. (1978, 1979). Data is given for most H II regions in the galactic longitude range 210 to 360 degrees that show 5GHz continuum brightness temperature exceeding 1K (as observed with the 4 arcminute beam of the Parkes 64-m telescope), together with a selection of sources that are weaker or outside of this longitude range. Tabulated data include source coordinates, peak brightness, flux density, and angular size from the 5GHz continuum survey; radial velocities of detected formaldehyde absorption lines; recombination line peak brightness, radial velocity, and line width; derived electron temperature assuming LTE; derived kinematic distance from the Sun and galactocentric radius; and presence or absence of a visible optical counterpart. In cases where kinematic distance is ambiguous, both near and far distances are tabulated; a flag is given if there is a strong preference for near or far distance based on information such as H I or H2CO absorption measurements or visibility of an optical counterpart. Many of these radio HII regions lie beyond the range of optical detection, at distances exceeding several kpc; they thus provide a comprehensive coverage of the southern HII regions in the Galaxy over the longitude range 210 to 360 degrees and constitute a vital data base for the study of galactic structure.
- ID:
- ivo://CDS.VizieR/J/A+AS/146/323
- Title:
- RASS young sources around R CrA
- Short Name:
- J/A+AS/146/323
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the ROSAT All-Sky Survey data in a 126 deg^2^ area in and around the CrA star forming region. With low-resolution spectroscopy of unidentified ROSAT sources we could find 19 new pre-main sequence stars, two of which are classical T Tauri stars, the others being weak-lined. The spectral types of these new T Tauri stars range from F7 to M6. The two new classical T Tauri stars are located towards two small cloud-lets outside of the main CrA cloud. They appear to be ~10 Myrs old, by comparing their location in the H-R diagram with isochrones for an assumed distance of 130 pc, the distance of the main CrA dark cloud. The new off-cloud weak-line T Tauri stars may have formed in similar cloudlets, which have dispersed recently. High-resolution spectra of our new T Tauri stars show that they have significantly more lithium absorption than zero-age main-sequence stars of the same spectral type, so that they are indeed young. From those spectra we also obtained rotational and radial velocities. For some stars we found the proper motion in published catalogs. The direction and velocity of the 3D space motion - south relative to the galactic plane - of the CrA T Tauri stars is consistent with the dark cloud being formed originally by a high-velocity cloud impact onto the galactic plane, which triggered the star formation in CrA. We also present VRIJHK photometry for most of the new T Tauri stars to derive their luminosities, ages, and masses.
- ID:
- ivo://CDS.VizieR/J/A+A/511/A90
- Title:
- RAVE DR2 distance catalogue
- Short Name:
- J/A+A/511/A90
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We develop a method for deriving distances from spectroscopic data and obtaining full 6D phase-space coordinates for the RAVE survey's second data release.
- ID:
- ivo://CDS.VizieR/J/A+A/600/A106
- Title:
- RAVE open cluster pairs, groups and complexes
- Short Name:
- J/A+A/600/A106
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Galactic open clusters (OCs) mainly belong to the young stellar population in the Milky Way disk, but are there groups and complexes of OCs that possibly define an additional level in hierarchical star formation? Current compilations are too incomplete to address this question, especially regarding radial velocities (RVs) and metallicities ([M/H]). Here we present the parameters for the final working sample of 432 open clusters, as well as the mean parameters for the 19 detected potential open cluster groupings.
1097. RAVE 3rd data release
- ID:
- ivo://CDS.VizieR/III/265
- Title:
- RAVE 3rd data release
- Short Name:
- III/265
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the third data release of the RAdial Velocity Experiment (RAVE) which is the first milestone of the RAVE project, releasing the full pilot survey. The catalog contains 83,072 radial velocity measurements for 77,461 stars in the southern celestial hemisphere, as well as stellar parameters for 39,833 stars. This paper describes the content of the new release, the new processing pipeline, as well as an updated calibration for the metallicity based upon the observation of additional standard stars. Spectra will be made available in a future release. The data release can be accessed via the RAVE Web site http://www.rave-survey.org.
1098. RAVE second data release
- ID:
- ivo://CDS.VizieR/III/257
- Title:
- RAVE second data release
- Short Name:
- III/257
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the second data release of the Radial Velocity Experiment (RAVE), an ambitious spectroscopic survey to measure radial velocities and stellar atmosphere parameters (temperature, metallicity, surface gravity, and rotational velocity) of up to one million stars using the 6dF multi-object spectrograph on the 1.2m UK Schmidt Telescope of the Anglo-Australian Observatory (AAO). The RAVE program started in 2003, obtaining medium resolution spectra (median R=7500) in the Ca-triplet region (8410-8795{AA}) for southern hemisphere stars drawn from the Tycho-2 and SuperCOSMOS catalogues, in the magnitude range 9<I<12. Following the first data release, the current release doubles the sample of published radial velocities, now containing 51829 radial velocities for 49327 individual stars observed on 141 nights between 2003 April 11 and 2005 March 31. Comparison with external data sets shows that the new data collected since 2004 April 3 show a standard deviation of 1.3km/s, about twice as good as for the first data release. For the first time, this data release contains values of stellar parameters from 22407 spectra of 21121 individual stars. They were derived by a penalized chi-square method using an extensive grid of synthetic spectra calculated from the latest version of Kurucz stellar atmosphere models. From comparison with external data sets, our conservative estimates of errors of the stellar parameters for a spectrum with an average signal-to-noise ratio (S/N) of ~40 are 400K in temperature, 0.5dex in gravity, and 0.2dex in metallicity. We note however that, for all three stellar parameters, the internal errors estimated from repeat RAVE observations of 855 stars are at least a factor 2 smaller. We demonstrate that the results show no systematic offsets if compared to values derived from photometry or complementary spectroscopic analyses. The data release includes proper motions from Starnet2, Tycho-2, and UCAC2 catalogs and photometric measurements from Tycho-2 USNO-B, DENIS, and 2MASS. The data release can be accessed via the RAVE Web site: http://www.rave-survey.org and through CDS.
- ID:
- ivo://CDS.VizieR/J/ApJ/737/9
- Title:
- RAVE spectroscopic data of stars in the thick disk
- Short Name:
- J/ApJ/737/9
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have undertaken the study of the elemental abundances and kinematic properties of a metal-poor sample of candidate thick-disk stars selected from the Radial Velocity Experiment spectroscopic survey of bright stars to differentiate among the present scenarios of the formation of the thick disk. In this paper, we report on a sample of 214 red giant branch, 31 red clump/horizontal branch, and 74 main-sequence/sub-giant branch metal-poor stars, which serves to augment our previous sample of only giant stars. We find that the thick disk [{alpha}/Fe] ratios are enhanced and have little variation (<0.1dex), in agreement with our previous study. The augmented sample further allows, for the first time, investigation of the gradients in the metal-poor thick disk.
1100. RAVE 6th data release
- ID:
- ivo://CDS.VizieR/III/283
- Title:
- RAVE 6th data release
- Short Name:
- III/283
- Date:
- 22 Feb 2022
- Publisher:
- CDS
- Description:
- The Radial Velocity Experiment (RAVE) is a magnitude-limited (9<I<12) spectroscopic survey of Galactic stars randomly selected in Earth's southern hemisphere. The RAVE medium-resolution spectra (R~7500) cover the Ca-triplet region (8410-8795{AA}). The sixth and final data release (DR6) is based on 518387 observations of 451783 unique stars. RAVE observations were taken between 2003 April 12 and 2013 April 4. Here we present the genesis, setup, and data reduction of RAVE as well as wavelength-calibrated and flux-normalized spectra and error spectra for all observations in RAVE DR6. Furthermore, we present derived spectral classification and radial velocities for the RAVE targets, complemented by cross-matches with Gaia DR2 and other relevant catalogs. A comparison between internal error estimates, variances derived from stars with more than one observing epoch, and a comparison with radial velocities of Gaia DR2 reveals consistently that 68% of the objects have a velocity accuracy better than 1.4km/s, while 95% of the objects have radial velocities better than 4.0km/s. We present part 2 of the sixth and final Data Release (DR6) of the Radial Velocity Experiment (RAVE), a magnitude-limited (9<I<12) spectroscopic survey of Galactic stars randomly selected in Earth's southern hemisphere. The RAVE medium-resolution spectra (R~7500) cover the Ca triplet region (8410-8795{AA}) and span the complete time frame from the start of RAVE observations on 2003 April 12 to their completion on 2013 April 4. In the second of two publications, we present the data products derived from 518,387 observations of 451,783 unique stars using a suite of advanced reduction pipelines focusing on stellar atmospheric parameters, in particular purely spectroscopically derived stellar atmospheric parameters (Teff, logg, and the overall metallicity), enhanced stellar atmospheric parameters inferred via a Bayesian pipeline using Gaia DR2 astrometric priors, and asteroseismically calibrated stellar atmospheric parameters for giant stars based on asteroseismic observations for 699 K2 stars. In addition, we provide abundances of the elements Fe, Al, and Ni, as well as an overall [alpha/Fe] ratio obtained using a new pipeline based on the GAUGUIN optimization method that is able to deal with variable signal-to-noise ratios. The RAVE DR6 catalogs are cross-matched with relevant astrometric and photometric catalogs, and are complemented by orbital parameters and effective temperatures based on the infrared flux method.