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22671. Walraven photometry in Sco-Cen association
ID:
ivo://CDS.VizieR/J/A+A/216/44
Title:
Walraven photometry in Sco-Cen association
Short Name:
J/A+A/216/44
Date:
21 Oct 2021
Publisher:
CDS
Description:
Walraven photometry is presented of established and probable members of the Scorpio-Centaurus OB association. For each star, effective temperature and surface gravity are derived using Kurucz atmosphere models (1979ApJS...40....1K). From the Straizys and Kuriliene (1981Ap&SS..80..353S) tables, absolute magnitudes are calculated. Distance moduli and visual extinctions are determined for all stars. From a comparison of the HR-diagrams of the stars in each subgroup with theoretical isochrones, the ages of the three subgroups are derived. The distances to the three subgroups are shown to be different; there is a general trend (also within each subgroup) for the distances to be larger at higher galactic longitudes. The visual extinction in the youngest subgroup Upper-Scorpius, is well correlated with the IRAS 100-micron map. The distance toward the Ophiuchus dark clouds is found to be 125 pc, based on the photometric distances to the stars. Most of the early-type stars in Upper-Scorpius are located at the far side of the dark clouds.
22672. Walraven photometry near AG Car
ID:
ivo://CDS.VizieR/J/A+AS/98/505
Title:
Walraven photometry near AG Car
Short Name:
J/A+AS/98/505
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present Walraven-photometric data of 114 stars of 5.9<V<14.7 within 17 arcmin of the Luminous Blue Variable AG Car (HD 94910). The results are expressed in terms of V-magnitude in the Johnson system and in observed and extinction-free colours in the Walraven system. For a description of the Walraven photometric system, see e.g. <GCPD/11>
22673. Walraven photometry of 8 Cataclysmic variables
ID:
ivo://CDS.VizieR/J/A+AS/101/87
Title:
Walraven photometry of 8 Cataclysmic variables
Short Name:
J/A+AS/101/87
Date:
21 Oct 2021
Publisher:
CDS
Description:
The files contain the results of the photometry observations obtained during July/August 1988 with the Walraven photometer on the 90cm telescope at ESO (La Silla). The brightness measurements are collected simultaneously in the 5 passbands VBLUW (544, 430, 384, 362 and 324nm) with integration times of 16s.
22674. Walraven photometry of OB stars
ID:
ivo://CDS.VizieR/J/A+A/369/527
Title:
Walraven photometry of OB stars
Short Name:
J/A+A/369/527
Date:
21 Oct 2021
Publisher:
CDS
Description:
About 700 stars, mostly OB-stars, were observed by the author at the former Leiden Southern Station at Hartebees poortdam, South Africa, in the observing seasons 1965, 1968, 1969, 1974, 1977, 1978. Observations were made in the five channels of the Walraven photometric system. Due to weathering of the telescope mirror the W channel gave no reliable results for the faintest stars (m=11mag); in these cases the U-W colour index is not given. The change in sensitivity in the V channel, supposedly having occurred in 1968, was not recognised. For a description of the Walraven VBLUW photometric system, see e.g. <GCPD/11>
22675. Walraven photometry of OB stars
ID:
ivo://CDS.VizieR/J/A+AS/137/113
Title:
Walraven photometry of OB stars
Short Name:
J/A+AS/137/113
Date:
21 Oct 2021
Publisher:
CDS
Description:
Observations of OB-stars, made in 1959 and 1960 at the Leiden Southern Station near Hartebeespoortdam, South Africa, with the VBLUW photometer attached to th e 90 cm light-collector, are given in this paper. They are compared with photome try obtained by Graham (1968BANS....2..397G), Walraven & Walraven (1977BAN....15...67W), Lub & Pel (1977A&A....54..137L) and van Genderen et al. (1984A&AS...58..537V). Formulae for the transformation of the present observations to those of Walraven & Walraven (1977BAN....15...67W) and Lub & Pel (1977A&A....54..137L) are given. For a description of the VBLUW photometric system, see e.g. <GCPD/11>
22676. Walraven Photometry of southern OB associations
ID:
ivo://CDS.VizieR/J/A+AS/85/915
Title:
Walraven Photometry of southern OB associations
Short Name:
J/A+AS/85/915
Date:
21 Oct 2021
Publisher:
CDS
Description:
Homogeneous Walraven (VBLUW) photometry is presented for 5260 stars in the region of five nearby southern OB associations: Sco-Cen (Sco OB2), Ori OB1, CMa OB1, Mon OB1, and Sct OB2. Note that the tables have been prepared at Lausanne/Geneve Observatory (star names in Lausanne/Geneva system, coordinates absent) For details about the Walraven photometric system, see <GCPD/11>
22677. Walraven photometry of WX Hyi
ID:
ivo://CDS.VizieR/J/A+A/242/401
Title:
Walraven photometry of WX Hyi
Short Name:
J/A+A/242/401
Date:
21 Oct 2021
Publisher:
CDS
Description:
The SU UMa-type dwarf nova WX Hyi was observed in the 5 passbands VBLUW (544, 430, 384, 362 and 324nm) during 15 nights on the 90cm telescope at ESO (La Silla), between July and November 1988, with an integration time of 16s.
22678. W Aql APEX spectrum
ID:
ivo://CDS.VizieR/J/A+A/642/A20
Title:
W Aql APEX spectrum
Short Name:
J/A+A/642/A20
Date:
23 Mar 2022 16:31:40
Publisher:
CDS
Description:
W Aql is an asymptotic giant branch (AGB) star with an atmospheric elemental abundance ratio C/O~=0.98. It has previously been reported to have circumstellar molecular abundances intermediate between those of M-type and C-type AGB stars, which respectively have C/O<1 and C/O>1. This intermediate status is considered typical for S-type stars, although our understanding of the chemical content of their circumstellar envelopes is currently rather limited. We wish to assess the reported intermediate status of W Aql by analysing the line emission of molecules that have not been observed towards this star before. We have performed observations in the frequency range 159-268GHz with the SEPIA/B5 and PI230 instruments on the APEX telescope. We make abundance estimates through direct comparison to available spectra towards a number of well-studied AGB stars and based on rotational diagram analysis in the case of one molecule. From a compilation of our abundance estimates and those found in the literature for two M-type (R Dor, IK Tau), two S-type ({chi} Cyg, W Aql), and two C-type stars (V Aql, IRC +10 216), we conclude that W Aql's circumstellar environment appears considerably closer to that of a C-type AGB star than to that of an M-type AGB star. In particular, we detect emission from C_2_H, SiC_2_, SiN, and HC_3_N, molecules previously only detected towards the circumstellar environment of C-type stars. This conclusion, based on the chemistry of the gaseous component of the circumstellar environment, is further supported by reports in the literature on the presence of atmospheric molecular bands and spectral features of dust species which are typical for C-type AGB stars. Although our observations mainly trace species in the outer regions of the circumstellar environment, our conclusion matches closely that based on recent chemical equilibrium models for the inner wind of S-type stars: the atmospheric and circumstellar chemistry of S-type stars likely resembles that of C-type AGB stars much more closely than that of M-type AGB stars. Further observational investigation of the gaseous circumstellar chemistry of S-type stars is required to characterise its dependence on the atmospheric C/O. Non-equilibrium chemical models of the circumstellar environment of AGB stars need to address the particular class of S-type stars and the chemical variety that is induced by the range in atmospheric C/O.
22679. Warm dust near methanol masers
ID:
ivo://CDS.VizieR/J/A+A/410/597
Title:
Warm dust near methanol masers
Short Name:
J/A+A/410/597
Date:
21 Oct 2021
Publisher:
CDS
Description:
Continuum emission at 450 and 850{mu}m from warm dust has been mapped in the fields of 71 methanol masers. Within these fields lie 30 centimetre-wave radio continuum sources and an additional 13 methanol maser sites. Sub-mm emission is detected at all but one of the maser sites, confirming the association of methanol maser emission with deeply embedded objects. Measured bolometric luminosities confirm that methanol maser emission is an excellent signpost of high-mass star formation. Examples of nearby isolated maserless dust cores may be harbouring massive protostars at an earlier evolutionary stage.
22680. Warm IRAS sources. I. AGN candidates
ID:
ivo://CDS.VizieR/J/A+AS/70/95
Title:
Warm IRAS sources. I. AGN candidates
Short Name:
J/A+AS/70/95
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have previously shown that a blue (warm) 60 to 25{mu}m infrared colour provides a powerful parameter for discriminating between AGNs and normal galaxies and that the far-IR spectrum is therefore an efficient tool for finding new AGNs (de Grijp et al., 1985Natur.314..140D) Here we present a list of such AGN candidates based on warm IR sources from the IRAS Point Source Catalogue (PSC, Cat. II/125). Identification data and finding charts are also given. In addition the list of warm IRAS sources is supplemented by a compendium of data from the IRAS PSC on detected sources identified with previously known AGNs whose infrared spectra do not bring them within our colour selection criterion

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