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- ID:
- ivo://CDS.VizieR/J/A+A/602/A53
- Title:
- R Aqr SPHERE/ZIMPOL narrow-H{alpha} image
- Short Name:
- J/A+A/602/A53
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- R Aqr is a symbiotic binary system consisting of a mira variable, a hot companion with a spectacular jet outflow, and an extended emission line nebula. Because of its proximity to the Sun, this object has been studied in much detail with many types of high resolution imaging and interferometric techniques. We have used R Aqr as test target for the visual camera subsystem ZIMPOL, which is part of the new extreme adaptive optics (AO) instrument SPHERE at the Very Large Telescope (VLT). We describe SPHERE/ZIMPOL test observations of the R Aqr system taken in H{alpha} and other filters in order to demonstrate the exceptional performance of this high resolution instrument. We compare our observations with data from the Hubble Space Telescope (HST) and illustrate the complementarity of the two instruments. We use our data for a detailed characterization of the inner jet region of R Aqr. We analyze the high resolution ~=25mas images from SPHERE/ZIMPOL and determine from the H{alpha} emission the position, size, geometric structure, and line fluxes of the jet source and the clouds in the innermost region <2"(<400AU) of R Aqr. The data are compared to simultaneous HST line filter observations. The H{alpha} fluxes and the measured sizes of the clouds yield H{alpha} emissivities for many clouds from which one can derive the mean density, mass, recombination time scale, and other cloud parameters. Our H{alpha} data resolve for the first time the R Aqr binary and we measure for the jet source a relative position 45 mas West (position angle -89.5{deg}) of the mira. The central jet source is the strongest H{alpha} component with a flux of about 2.5x10^-12^erg/cm^2^/s. North east and south west from the central source there are many clouds with very diverse structures. Within 0.5" (100AU) we see in the SW a string of bright clouds arranged in a zig-zag pattern and, further out, at 1"-2", fainter and more extended bubbles. In the N and NE we see a bright, very elongated filamentary structure between 0.2"-0.7" and faint perpendicular "wisps" further out. Some jet clouds are also detected in the ZIMPOL [OI] and HeI filters, as well as in the HST-WFC3 line filters for H{alpha}, [OIII], [NII], and [OI]. We determine jet cloud parameters and find a very well defined correlation Ne{prop.to}r^-1.3^ between cloud density and distance to the central binary. Densities are very high with typical values of Ne~=3x10^5^cm^-3^ for the "outer" clouds around 300AU, Ne~=3x10^6^cm^-3^ for the "inner" clouds around 50AU, and even higher for the central jet source. The high Ne of the clouds implies short recombination or variability timescales of a year or shorter. H{alpha} high resolution data provide a lot of diagnostic information for the ionized jet gas in R Aqr. Future H{alpha} observations will provide the orientation of the orbital plane of the binary and allow detailed hydrodynamical investigations of this jet outflow and its interaction with the wind of the red giant companion.
- 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.
5484. 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.
5485. 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.
5486. 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.
5487. RAVE 4th data release
- ID:
- ivo://CDS.VizieR/III/272
- Title:
- RAVE 4th data release
- Short Name:
- III/272
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the stellar atmospheric parameters (effective temperature, surface gravity, overall metallicity), radial velocities, individual abundances, and distances determined for 425,561 stars, which constitute the fourth public data release of the RAdial Velocity Experiment (RAVE). The stellar atmospheric parameters are computed using a new pipeline, based on the algorithms of MATISSE and DEGAS. The spectral degeneracies and the Two Micron All Sky Survey photometric information are now better taken into consideration, improving the parameter determination compared to the previous RAVE data releases. The individual abundances for six elements (magnesium, aluminium, silicon, titanium, iron, and nickel) are also given, based on a special-purpose pipeline that is also improved compared to that available for the RAVE DR3 and Chemical DR1 data releases. The data release can also be accessed via the RAVE Web site http://www.rave-survey.org.
5488. RAVE 5th data release
- ID:
- ivo://CDS.VizieR/III/279
- Title:
- RAVE 5th data release
- Short Name:
- III/279
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Data Release 5 (DR5) of the Radial Velocity Experiment (RAVE) is the fifth data release from a magnitude-limited (9<I<12) survey of stars randomly selected in the southern hemisphere. The RAVE medium-resolution spectra (R=7500) covering the Ca-triplet region (8410-8795A) span the complete time frame from the start of RAVE observations in 2003 to their completion in 2013. Radial velocities from 520,781 spectra of 457,588 unique stars are presented, of which 215,590 unique stars have parallaxes and proper motions from the Tycho-Gaia astrometric solution (TGAS) in Gaia DR1. For our main DR5 catalog, stellar parameters (effective temperature, surface gravity, overall metallicity) are computed using the RAVE DR4 stellar pipeline, but calibrated using recent K2 Campaign 1 seismic gravities and Gaia benchmark stars, as well as results obtained from high-resolution studies. Also included are temperatures from the Infrared Flux Method, and we provide a catalogue of red giant stars in the dereddened color (J-Ks)0 interval (0.50,0.85) for which the gravities were calibrated based only on seismology. Further data products for sub-samples of the RAVE stars include individual abundances for Mg, Al, Si, Ca, Ti, Fe, and Ni, and distances found using isochrones. Each RAVE spectrum is complemented by an error spectrum, which has been used to determine uncertainties on the parameters.
- ID:
- ivo://CDS.VizieR/J/ApJ/768/40
- Title:
- R-band and polarimetry of the blazar S5 0716+71
- Short Name:
- J/ApJ/768/40
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of optical (R band) photometric and polarimetric monitoring and Very Long Baseline Array (VLBA) imaging of the blazar S5 0716+714 along with Fermi {gamma}-ray data during a multi-waveband outburst in 2011 October. We analyze total and polarized intensity images of the blazar obtained with the VLBA at 43GHz during and after the outburst. Monotonic rotation of the linear polarization vector at a rate of >~50{deg} per night coincided with a sharp maximum in {gamma}-ray and optical flux. At the same time, within the uncertainties, a new superluminal knot appeared with an apparent speed of 21+/-2c. The general multi-frequency behavior of the outburst can be explained within the framework of a shock wave propagating along a helical path in the blazar's jet.
- ID:
- ivo://CDS.VizieR/J/ApJS/234/37
- Title:
- R-band K2 photometry of main-belt asteroids
- Short Name:
- J/ApJS/234/37
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the K2 light curves of a large sample of untargeted main-belt asteroids (MBAs) detected with the Kepler Space Telescope. The asteroids were observed within the Uranus superstamp, a relatively large, continuous field with a low stellar background designed to cover the planet Uranus and its moons during Campaign 8 of the K2 mission. The superstamp offered the possibility of obtaining precise, uninterrupted light curves of a large number of MBAs and thus determining unambiguous rotation rates for them. We obtained photometry for 608 MBAs, and were able to determine or estimate rotation rates for 90 targets, of which 86 had no known values before. In an additional 16 targets we detected incomplete cycles and/or eclipse-like events. We found the median rotation rate to be significantly longer than that of the ground-based observations, indicating that the latter are biased toward shorter rotation rates. Our study highlights the need and benefits of further continuous photometry of asteroids.
