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17331. Well sampled stars FEROS+HARPS radial velocities
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.
17332. WERGS. II. SED fitting with optical, IR & radio data
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.
17333. Westerbork in the Southern Hemisphere (WISH) Source Catalog
ID:
ivo://nasa.heasarc/wish
Title:
Westerbork in the Southern Hemisphere (WISH) Source Catalog
Short Name:
WISH
Date:
01 Nov 2024
Publisher:
NASA/GSFC HEASARC
Description:
The Westerbork in the Southern Hemishpere (WISH) is a low-frequency (352 MHz) radio survey that covers most of the sky (the Galactic Plane region |b| &lt; 10 degrees is excluded) between -26 and -9 degrees (1.60 sr) at a wavelength of 92 cm to a limiting flux density of approximately 18 mJy (5 sigma). WISH is the southern extension of the Westerbork Northern Sky Survey (WENSS). Due to the very low elevation of the observations, the survey has a much lower resolution in declination than in right ascension (54&quot; x 54&quot; cosec[delta]). A correlation with the 1.4GHz NVSS (&lt;a href="https://cdsarc.cds.unistra.fr/ftp/cats/VIII/65"&gt;CDS Cat. VIII/65&lt;/a&gt;) shows that the positional accuracy is less constrained in declination than in right ascension, but there is no significant systematic error. This table contains 90,357 352-MHz flux density measurements, some of them being multiple observations of the same sources, some of them measurements of individual components of multi-component sources. While the abstract of the reference paper states that there are 73,570 sources in this catalog, the HEASARC counts 77,414 unique sources in this version of the table. The correlation with the NVSS was also used to construct a sample of faint Ultra Steep Spectrum sources (Table 2 in the reference paper, available at &lt;a href="http://cdsarc.u-strasbg.fr/ftp/cats/VIII/69A/uss.dat.gz"&gt;http://cdsarc.u-strasbg.fr/ftp/cats/VIII/69A/uss.dat.gz&lt;/a&gt;). This sample is aimed at increasing the number of known high redshift radio galaxies to allow detailed follow-up studies of these massive galaxies and their environments in the early Universe. WISH is a collaboration between the Netherlands Foundation for Research in Astronomy (NFRA/ASTRON) and the Leiden Observatory. Carlos De Breuck, Yuan Tang, Ger de Bruyn, Huub Rottgering, Wil van Breugel, and Roeland Rengelink. For more information, see the WENSS home page at &lt;a href="http://www.astron.nl/wow/testcode.php?survey=1"&gt;http://www.astron.nl/wow/testcode.php?survey=1&lt;/a&gt;. This table was created by the HEASARC in November 2010 base on &lt;a href="https://cdsarc.cds.unistra.fr/ftp/cats/VIII/69A"&gt;CDS catalog VIII/69A&lt;/a&gt; file wish11.dat. This is a service provided by NASA HEASARC .
17334. Westerbork Northern Sky Survey
ID:
ivo://nasa.heasarc/wenss
Title:
Westerbork Northern Sky Survey
Short Name:
WENSS
Date:
01 Nov 2024
Publisher:
NASA/GSFC HEASARC
Description:
The Westerbork Northern Sky Survey (WENSS) is a low-frequency radio survey that covers the whole sky north of declination +30 degrees at a wavelength of 92 cm to a limiting flux density of approximately 18 milliJanskies (mJy) at the 5 sigma level. WENSS is a collaboration between the Netherlands Foundation for Research in Astronomy (NFRA/ASTRON) and the Leiden Observatory. The major personnel involved in WENSS include Ger de Bruyn, George Miley, Roeland Rengelink, Yuan Tang, Malcolm Bremer, Huub Rottgering, Ernst Raimond, Martin Bremer, and David Fullagar. The version of the WENSS Catalog as implemented at the HEASARC is a union of two separate catalogs obtained from the WENSS Website: the WENSS Polar Catalog (18186 sources above +72 degrees declination) and the WENSS Main Catalog (211234 sources in the declination region from +28 to +76 degrees). This database table was created by the HEASARC in February 2001 based on the tables wenssn10.cat (WENSS Main Catalog) and wenssp10.cat (WENSS Polar Catalog) obtained from the WENSS web site at &lt;a href="http://www.strw.leidenuniv.nl/"&gt;http://www.strw.leidenuniv.nl/&lt;/a&gt;. This is a service provided by NASA HEASARC .
17335. Westerbork Northern Sky Survey I.
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.
17336. Westerbork observations of Galactic Sources
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.
17337. Westerbork Second Deep Survey
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.
17338. Westerhout's Catalogue of 82 Discrete Sources
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.
17339. Westerlund 1 Chandra X-Ray Point Source Catalog
ID:
ivo://nasa.heasarc/wd1cxo
Title:
Westerlund 1 Chandra X-Ray Point Source Catalog
Short Name:
WD1CXO
Date:
01 Nov 2024
Publisher:
NASA/GSFC HEASARC
Description:
The nature of the X-ray point source population within the young massive cluster Westerlund 1 (Wd 1) is investigated. Chandra X-ray Observatory (CXO) observations were used to determine the X-ray properties of emitters within Wd 1, while a comprehensive multi-wavelength dataset was employed to constrain their nature. Wd 1 (l=339.5, b=-0.4) was observed with the CXO Advanced CCD Spectrometer Spectroscopic array on 2005 May 22 for 18 ks (sequence 6283) and 2005 June 20 for 42 ks (sequence 5411). 241 sources were found above a sensitivity threshold that corresponded to a 10&lt;sup&gt;-6&lt;/sup&gt; chance per PSF element of detecting a spurious source. X-ray emission from a multitude of different stellar sources within Wd 1, including both evolved high mass and low-mass pre-MS stars, is found. This table was created by the HEASARC in May 2008 based on CDS table J/A+A/477/147 files table1.dat and table3.dat. This is a service provided by NASA HEASARC .
17340. 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.

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