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24831. W3 star-forming region 345 GHz survey
ID:
ivo://CDS.VizieR/J/A+AS/124/205
Title:
W3 star-forming region 345 GHz survey
Short Name:
J/A+AS/124/205
Date:
21 Oct 2021
Publisher:
CDS
Description:
Results are presented of the 345 GHz spectral survey toward three sources in the W 3 Giant Molecular Cloud: W 3 IRS4, W 3 IRS5 and W 3(H_2_O). Nearly 90% of the atmospheric window between 334 and 365GHz has been scanned using the James Clerk Maxwell Telescope (JCMT) down to a noise level of ~80mK per resolution element. These observations are complemented by a large amount of data in the 230GHz atmospheric window. From this data set physical conditions and beam-averaged column densities are derived for more than 14 chemically different species (over 24 different isotopes). The physical parameters derived in Paper I (Helmich et al., 1994A&A...283..626H) are confirmed by the analysis of the excitation of other species, although there is evidence that the silicon- and sulfur-bearing molecules exist in a somewhat denser and warmer environment. The densities are high, >=10^6^cm^-3^, in the three sources and the kinetic temperatures for the bulk of the gas range from 55K for IRS4 to 220K for W 3(H_2_O). The chemical differences between the three sources are very striking: silicon- and sulfur-bearing molecules such as SiO and SO_2_ are prominent toward IRS5, whereas organic molecules like CH_3_OH, CH_3_OCH_3_ and CH_3_OCHO are at least an order of magnitude more abundant toward W 3(H_2_O). Vibrationally excited molecules are also detected toward this source. Only simple molecules are found toward IRS4. The data provide constraints on the amount of deuterium fractionation and the ionization fraction in the observed regions as well. These chemical characteristics are discussed in the context of an evolutionary sequence, in which IRS5 is the youngest, W 3(H_2_O) somewhat older and IRS4, although still enigmatic, the oldest.
24832. W UMa type and CAB stars dynamical evolution
ID:
ivo://CDS.VizieR/J/MNRAS/373/1483
Title:
W UMa type and CAB stars dynamical evolution
Short Name:
J/MNRAS/373/1483
Date:
21 Oct 2021
Publisher:
CDS
Description:
Orbital angular momentum (OAM, Jo), systemic mass (M) and orbital period (P) distributions of chromospherically active binaries (CAB) and W Ursae Majoris (W UMa) systems were investigated. The diagrams of and logJo-logP, logM-logP and logJo-logM were formed from 119 CAB and 102 W UMa stars. The log Jo-logM diagram is found to be most meaningful in demonstrating dynamical evolution of binary star orbits. A slightly curved borderline (contact border) separating the detached and the contact systems was discovered on the logJo-logM diagram. Since the orbital size (a) and period (P) of binaries are determined by their current Jo, M and mass ratio, q, the rates of OAM loss (dlogJo/dt) and mass loss (dlogM/dt) are primary parameters to determine the direction and the speed of the dynamical evolution. A detached system becomes a contact system if its own dynamical evolution enables it to pass the contact border on the logJo-logM diagram. The evolution of q for a mass-losing detached system is unknown unless the mass-loss rate for each component is known. Assuming q is constant in the first approximation and using the mean decreasing rates of Jo and M from the kinematical ages of CAB stars, it has been predicted that 11, 23 and 39 per cent of current CAB stars would transform to W UMa systems if their nuclear evolution permits them to live 2, 4 and 6Gyr, respectively.
24833. W UMa-type contact binaries ages and masses
ID:
ivo://CDS.VizieR/J/MNRAS/437/185
Title:
W UMa-type contact binaries ages and masses
Short Name:
J/MNRAS/437/185
Date:
21 Oct 2021
Publisher:
CDS
Description:
Recently, our understanding of the origin of W UMa-type contact binaries has become clearer. Initial masses of their components were successfully estimated by Yildiz and Dogan using a new method mainly based on observational properties of overluminous secondary components. In this paper, we continue to discuss the results and make computations for age and orbital evolution of these binaries. It is shown that the secondary mass, according to its luminosity, also successfully predicts the observed radius. While the current mass of the primary component is determined by initial masses, the current secondary mass is also a function of initial angular momentum. We develop methods to compute the age of A- and W-subtype W UMa-type contact binaries in terms of initial masses and mass according to the luminosity of the secondaries. Comparisons of our results with the mean ages from kinematic properties of these binaries and data pertaining to contact binaries in open and globular clusters have increased our confidence on this method. The mean ages of both A- and W-subtype contact binaries are found as 4.4 and 4.6Gyr, respectively. From kinematic studies, these ages are given as 4.5 and 4.4Gyr, respectively. We also compute orbital properties of A-subtype contact binaries at the time of the first overflow. Initial angular momentum of these binaries is computed by comparing them with the well-known detached binaries. The angular momentum loss rate derived in the present study for the detached phase is in very good agreement with the semi-empirical rates available in the literature. In addition to the limitations on the initial masses of W UMa-type contact binaries, it is shown that the initial period of these binaries is less than about 4.45d.
24834. W Virginis high-resolution spectra
ID:
ivo://CDS.VizieR/J/A+A/526/A116
Title:
W Virginis high-resolution spectra
Short Name:
J/A+A/526/A116
Date:
21 Oct 2021
Publisher:
CDS
Description:
The aim of this work was to perform a multiphase spectroscopic study of W Vir which represents stars of the class of Population II cepheids, in order to trace the behaviour of emission features in different lines, and to use the data to describe the dynamical processes in the atmosphere of this star associated with the shock wave propagation.
24835. WWFI g'-band obs. of bright cluster galaxies
ID:
ivo://CDS.VizieR/J/ApJS/247/43
Title:
WWFI g'-band obs. of bright cluster galaxies
Short Name:
J/ApJS/247/43
Date:
21 Oct 2021
Publisher:
CDS
Description:
Observations of 170 local (z<~0.08) galaxy clusters in the northern hemisphere have been obtained with the Wendelstein Telescope Wide Field Imager (WWFI). We correct for systematic effects such as point-spread function broadening, foreground star contamination, relative bias offsets, and charge persistence. Background inhomogeneities induced by scattered light are reduced down to {Delta}SB>31 g' mag/arcsec^2^ by large dithering and subtraction of night-sky flats. Residual background inhomogeneities brighter than SB_{sigma}_<27.6 g' mag/arcsec^2^ caused by galactic cirrus are detected in front of 23% of the clusters. However, the large field of view allows discrimination between accretion signatures and galactic cirrus. We detect accretion signatures in the form of tidal streams in 22%, shells in 9.4%, and multiple nuclei in 47% of the brightest cluster galaxies (BCGs) and find two BCGs in 7% of the clusters. We measure semimajor-axis surface brightness profiles of the BCGs and their surrounding intracluster light (ICL) down to a limiting surface brightness of SB=30 g' mag/arcsec^2^. The spatial resolution in the inner regions is increased by combining the WWFI light profiles with those that we measured from archival Hubble Space Telescope images or deconvolved WWFI images. We find that 71% of the BCG+ICL systems have surface brightness (SB) profiles that are well described by a single Sersic function, whereas 29% require a double Sersic function to obtain a good fit. We find that BCGs have scaling relations that differ markedly from those of normal ellipticals, likely due to their indistinguishable embedding in the ICL.
24836. WWFI g'-band obs. of bright galaxy clusters
ID:
ivo://CDS.VizieR/J/ApJS/252/27
Title:
WWFI g'-band obs. of bright galaxy clusters
Short Name:
J/ApJS/252/27
Date:
21 Oct 2021
Publisher:
CDS
Description:
We explore several ways to dissect brightest cluster galaxies (BCGs) and their surrounding intracluster light (ICL) using a surface brightness (SB) cut, a luminosity cut, excess light above a de Vaucouleurs profile, or a double Sersic decomposition. Assuming that all light above M{<}-21.85g'mag is attributable to the ICL, we find that an average fraction of f_ICL_^MT^=71+/-22% of all diffuse light centered on the BCG belongs to the ICL. Likewise, if we assume that all light fainter than SB>27g'mag/arcsec^2^ belongs to the ICL, the average ICL fraction is f_ICL_^SB27^=34+/-19% . After fitting a de Vaucouleurs profile to the inner parts of the SB profile, we detect excess light at large radii, corresponding to an average ICL fraction of f_ICL_^DV^=48+/-20% . Finally, by decomposing the SB profile into two Sersic functions, we find an average ICL fraction of f_ICL_^Sx^=52+/-21% associated with the outer Sersic component. Our measured ICL and BCG+ICL luminosities agree well with predictions from high-resolution simulations where the outer Sersic component traces the unrelaxed, accreted stellar material. BCG and ICL properties defined in this way are correlated with cluster parameters to study the coevolution of BCGs, ICL, and their host clusters. We find positive correlations between BCG+ICL brightness and cluster mass, cluster velocity dispersion, cluster radius, and integrated satellite brightness, confirming that BCG/ICL growth is indeed coupled with cluster growth. On average, the ICL is better aligned than the BCG with the host cluster in terms of position angle, ellipticity, and centering. That makes it a potential dark-matter tracer.
24837. WW Vul B light curve during 1898-1966
ID:
ivo://CDS.VizieR/J/A+AS/120/429
Title:
WW Vul B light curve during 1898-1966
Short Name:
J/A+AS/120/429
Date:
21 Oct 2021
Publisher:
CDS
Description:
Photographic magnitudes are presented for the irregular variable WW Vulpeculae. They were derived from Argelander brightness estimates carried out on N=2774 plates of the Harvard College Observatory Plate Collection. The data set covers the period 1898 to 1966.
24838. www.plate-archive.org
ID:
ivo://www.plate-archive.org/web
Title:
www.plate-archive.org
Date:
28 Dec 2023
Publisher:
Leibniz Institute for Astrophysics Potsdam (AIP)
Description:
The main web service for www.plate-archive.org.
24839. www.plate-archive.org
ID:
ivo://www.plate-archive.org
Title:
www.plate-archive.org
Date:
28 Dec 2023
Publisher:
Leibniz Institute for Astrophysics Potsdam (AIP)
Description:
The authority for www.plate-archive.org.
24840. WX Pyx J-band light curve
ID:
ivo://CDS.VizieR/J/other/BASI/39.259
Title:
WX Pyx J-band light curve
Short Name:
J/other/BASI/39.
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present near-infrared J-band photometric observations of the intermediate polar WX Pyx. The frequency analysis indicates the presence of a period at 1559.2+/-0.2s which is attributed to the spin period of the white dwarf. The spin period inferred from the infrared data closely matches that determined from X-ray and optical observations. WX Pyx is a system whose orbital period has not been measured directly and which is not too well constrained. From the IR observations, a likely peak at 5.30+/-0.02h is seen in the power spectrum of the object. It is suggested that this corresponds to the orbital period of the system. In case this is indeed the true orbital period, some of the system physical parameters may be estimated. Our analysis indicates that the secondary star is of M2 spectral type and the distance to the object is 1.53kpc. An upper limit of 30 for the angle of inclination of the system is suggested. The mass transfer rate and the magnetic moment of the white dwarf are estimated to be (0.95-1.6)x10^-9^M_{sun}/yr and (1.9-2.4)x10^33^G*cm^3^ respectively.

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