- ID:
- ivo://CDS.VizieR/III/190B
- Title:
- WEB Catalog of Radial Velocities
- Short Name:
- III/190B
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We give a common version of the two catalogues of Mean Radial Velocities by Wilson (1953; catalogue <III/21>) and Evans (1978; catalogue <III/47>) to which we have added the catalogue of spectroscopic binary systems (Batten et al. 1989; catalogue <V/64>). For each star, when possible, we give: 1) an acronym to enter SIMBAD (Set of Identifications Measurements and Bibliography for Astronomical Data; see <http://cdsweb.u-strasbg.fr/Simbad.html>) of the CDS (Centre de Donnees Astronomiques de Strasbourg). 2) the number HIC of the HIPPARCOS catalogue (Turon 1992; catalogue <I/196>). 3) the CCDM number (Catalogue des Composantes des etoiles Doubles et Multiples) by Dommanget & Nys (1994; catalogue <I/211>). For the cluster stars, a precise study has been done, on the identification numbers. Numerous remarks point out the problems we have had to deal with.
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21352. WeCAPP Survey. M31 variables
- ID:
- ivo://CDS.VizieR/J/A+A/445/423
- Title:
- WeCAPP Survey. M31 variables
- Short Name:
- J/A+A/445/423
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The observations in the WeCAPP microlensing survey towards the Andromeda galaxy (M31) for a period of three years (2000-2003) resulted in a database with unprecedented time coverage for an extragalactic variable star study. We have monitored a 16.1' x 16.6' field centered on the nucleus of M31 in two optical bands (R and I) using the 0.8-m telescope at Wendelstein, Germany and the 1.2-m telescope at Calar Alto, Spain. Using the difference imaging method we detected 23781 variable sources for which we calculated the periods and variation amplitudes. We classified the variables according to their position in the R-band period-amplitude plane. Three groups can be distinguished; while the first two groups can be mainly associated with Cepheid-like variables (population I Cepheids in group I; type II Cepheids and RV Tauri stars in group II), the third one consists of Long Period Variables (LPVs). We detected 37 RV Tauri stars and 11 RV Tauri candidates, which makes this catalogue one of the largest collections of this class of stars to date. The classification scheme is supported by Fourier decomposition of the light curves. The catalogue of variable stars contains the positions, the periods in R and I, the significance of the assigned periods, and the variation amplitudes in the R and I bands.
- ID:
- ivo://CDS.VizieR/J/A+A/632/A37
- Title:
- Well sampled stars FEROS+HARPS radial velocities
- Short Name:
- J/A+A/632/A37
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Stars show various amounts of Radial Velocity (RV) jitter due to varying stellar activity levels. The typical amount of RV jitter as a function of stellar age and observational timescale has not been systematically quantified so far, although it is often larger than the instrumental precision of modern high-resolution spectrographs used for Doppler planet detection and characterization. We aim to empirically determine the intrinsic stellar RV variation for mostly G and K dwarf stars on different timescales and for different stellar ages independently of stellar models. We also focus on young stars (~<30Myr), where the RV variation is known to be large. We use archival FEROS and HARPS RV data of stars which were observed at least 30 times spread over at least two years. We then apply the Pooled Variance (PV) technique to these data sets to identify the periods and amplitudes of underlying, quasiperiodic signals. We show that the PV is a powerful tool to identify quasiperiodic signals in highly irregularly sampled data sets. We derive activity-lag functions for 20 assumingly single stars stars, where lag is the timescale on which the stellar jitter is measured. Since the ages of all stars are known, we also use this to formulate an activity-age-lag relation which can be used to predict the expected RV jitter of a star given its age and the timescale to be probed. The maximum RV jitter on timescales of decades decreases from over 500m/s for 5Myr old stars to 2.3m/s for stars with ages around 5Gyr. The decrease in RV jitter when considering a time scale of only 1d instead of 1yr is smaller by roughly a factor of 4 for stars with an age of about 5Myr, and a factor of 1.5 for stars with an age of 5Gyr. How fast the RV jitter increases with lag strongly depends on stellar age and reaches 99% of the maximum RV jitter between a few days for a few Myr old stars up to presumably decades or longer for stars with an age of a few Gyr.
- ID:
- ivo://CDS.VizieR/J/ApJS/243/15
- Title:
- WERGS. II. SED fitting with optical, IR & radio data
- Short Name:
- J/ApJS/243/15
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present physical properties of radio galaxies (RGs) with f_1.4GHz_>1mJy discovered by Subaru Hyper Suprime-Cam (HSC) and Very Large Array Faint Images of the Radio Sky at Twenty-Centimeters (FIRST) survey. For 1056 FIRST RGs at 0<z<=1.7 with HSC counterparts in about 100deg^2^, we compiled multi-wavelength data of optical, near-infrared (IR), mid-IR, far-IR, and radio (150MHz). We derived their color excess (E(B-V)_*_), stellar mass, star formation rate (SFR), IR luminosity, the ratio of IR and radio luminosity (q_IR_), and radio spectral index ({alpha}_radio_) that are derived from the spectral energy distribution (SED) fitting with CIGALE. We also estimated Eddington ratio based on stellar mass and integration of the best-fit SEDs of active galactic nucleus (AGN) component. We found that E(B-V)_*_, SFR, and IR luminosity clearly depend on redshift while stellar mass, q_IR_, and {alpha}_radio_ do not significantly depend on redshift. Since optically faint (i_AB_>=21.3) RGs that are newly discovered by our RG survey tend to be high redshift, they tend to not only have a large dust extinction and low stellar mass but also have high SFR and AGN luminosity, high IR luminosity, and high Eddington ratio compared with optically bright ones. The physical properties of a fraction of RGs in our sample seem to differ from a classical view of RGs with massive stellar mass, low SFR, and low Eddington ratio, demonstrating that our RG survey with HSC and FIRST provides us curious RGs among entire RG population.
- ID:
- ivo://CDS.VizieR/J/A+AS/124/259
- Title:
- Westerbork Northern Sky Survey I.
- Short Name:
- J/A+AS/124/259
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Westerbork Nortern Sky Survey (WENSS) is a low-frequency (325 MHz) radio survey that will cover the whole sky north of a declination of 30 degrees A first installment of the survey covers an area of 570 square degrees around the North Ecliptic Pole. A source list comprising 11,299 sources and 994 components is listed in Table 6 of the paper. This table is presented here.
- ID:
- ivo://CDS.VizieR/J/A+AS/43/1
- Title:
- Westerbork observations of Galactic Sources
- Short Name:
- J/A+AS/43/1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of a search for new Galactic sources from the BG catalogue (Fanti et al., 1974A&AS...16...43F). The observations were made with the Westerbork Synthesis Radiotelescope operating at 1.4GHz, using the short cuts technique. The adopted selection criteria for the observed sample are discussed in detail. For reducing the data we have adopted the Clean and Restore technique. We have also tested the capability of this technique in reproducing the total flux density for the very extended structures. A catalogue of the sources present in each field was produced ; the relevant information about observations and reduction characteristics are given.
- ID:
- ivo://CDS.VizieR/J/A+A/35/393
- Title:
- Westerbork Second Deep Survey
- Short Name:
- J/A+A/35/393
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A radio survey has been made of an area centered at 01h 03min +29{deg}, using the Westerbork telescope at 1415MHz. The completeness limit of the survey is 7mJy. Additional observations have been made at 610MHz. The Lick 120" telescope has been used to obtain deep (O98-O2 emulsion) plates to serve as an optical counterpart. A catalogue is presented of 58 sources found in the survey. 53 of these comprise a complete sample. 31 sources of the complete sample lie in areas of which Lick plates were taken. Of the sources in Lick plates areas, 11 could be identified with galaxies and 3 with possible QSO's, yielding an identification percentage of 46. For the other 22 sources an identification programme was carried out using Palomar Sky Survey prints and other large 48" Schmidt plates: three of these sources could be identified with galaxies and two with possible QSO's. The survey was also used to derive source counts and a spectral index distribution. The source counts agree well with those derived for an earlier survey. The spectral index distribution has a mean of 0.52 and a width of 0.39. the explanation for the flatter spectra is not clear but might possibly lie in another source population that begins to dominate the results at low flux densities.
- ID:
- ivo://CDS.VizieR/VIII/64
- Title:
- Westerhout's Catalogue of 82 Discrete Sources
- Short Name:
- VIII/64
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalogue was created based on the original published catalogue in the article by Westerhout G., 1958, Bull. Astron. Inst. Netherlands, vol.14, p.215, "A Survey of the Continuous Radiation from the Galactic System at a Frequency of 1390 Mc/s." His article describes the results of a survey of the radiation along the galactic ridge and a search for discrete sources. The observations were made with the 25-m radio telescope at Dwingeloo, which has a beamwidth of 0.57 degree at a frequency of 1390 Mc/s. The catalogue contains positions of 82 discrete sources. The epoch for positions in the original published catalogue was 1957.0. Positions referred to 2000.0 are shown in this machine-readable catalogue.
21359. Westerlund 2 JHKs photometry
- ID:
- ivo://CDS.VizieR/J/A+A/466/137
- Title:
- Westerlund 2 JHKs photometry
- Short Name:
- J/A+A/466/137
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Photometry for the stars detected with SOFI, NTT in J, H and Ks in the field containing the massive cluster Westerlund 2 (also know as RCW 49) associated with the HII region Gum29. For each star detected in all three bands the table contains the ID, equatorial coordinates, J, H and Ks magnitude and photometric errors. For the stars detected only in Ks or in H and Ks the magnitude and photometric error fields in the absent bands are filled with the values 99.99 and 9.999 respectively.
- ID:
- ivo://CDS.VizieR/J/A+A/632/A38
- Title:
- Westerlund 1 reduced images of radio emission
- Short Name:
- J/A+A/632/A38
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Massive stars and their stellar winds are important for a number of feedback processes. The mass lost in the stellar wind can help determine the end-point of the star as a neutron star (NS) or a black hole (BH). However, the impact of mass loss on the post-main sequence evolutionary stage of massive stars is not well understood. Westerlund 1 is an ideal astrophysical laboratory in which to study massive stars and their winds in great detail over a large range of different evolutionary phases. We aim to study the radio emission from Westerlund 1, in order to measure radio fluxes from the population of massive stars, and determine the mass-loss rates and spectral indices where possible. Observations were carried out in 2015 and 2016 with the Australia Telescope Compact Array (ATCA) at 5.5 and 9GHz using multiple configurations, with maximum baselines ranging from 750m to 6km. Thirty stars are detected in the radio from the fully concatenated dataset, ten of which are Wolf Rayet stars (WRs) (predominantly late type WN stars), five yellow hypergiants (YHGs), four red supergiants (RSGs), one luminous blue variable (LBV), the sgB[e] star W9, and several OB supergiants. New source detections in the radio are found for the WR stars, and five OB supergiants. These detections lead to evidence for three new OB supergiant binary candidates, which is inferred from derived spectral index limits. Spectral indices and index limits were determined for massive stars in Westerlund 1. For cluster members found to have partially optically thick emission, mass-loss rates were calculated. Under the approximation of a thermally emitting stellar wind and a steady mass-loss rate, clumping ratios were then estimated for eight WRs. Diffuse radio emission was detected throughout the cluster. Detections of knots of radio emission with no known counterparts indicate the highly clumped structure of this intra-cluster medium, likely shaped by a dense cluster wind.
