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6571. SWIRE Photometric Redshift Catalogue
ID:
ivo://CDS.VizieR/II/290
Title:
SWIRE Photometric Redshift Catalogue
Short Name:
II/290
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the SWIRE Photometric Redshift Catalogue 1025119 redshifts of unprecedented reliability and of accuracy comparable with or better than previous work. Our methodology is based on fixed galaxy and quasi-stellar object templates applied to data at 0.36-4.5um, and on a set of four infrared emission templates fitted to infrared excess data at 3.6-170um. The galaxy templates are initially empirical, but are given greater physical validity by fitting star formation histories to them, which also allows us to estimate stellar masses.
6572. SWIRE/SDSS quasars
ID:
ivo://CDS.VizieR/J/MNRAS/386/1252
Title:
SWIRE/SDSS quasars
Short Name:
J/MNRAS/386/1252
Date:
21 Oct 2021
Publisher:
CDS
Description:
We derive the properties of dusty tori in active galactic nuclei from the comparison of observed spectral energy distributions (SEDs) of SDSS quasars and a precomputed grid of torus models. The observed SEDs comprise SDSS photometry, Two-Micron All-Sky Survey J, H and K data, whenever available, and mid-infrared (mid-IR) data from the Spitzer Wide-area InfraRed Extragalactic Survey.
6573. SWIRE/SDSS quasars. II. Type 2 AGN
ID:
ivo://CDS.VizieR/J/MNRAS/399/1206
Title:
SWIRE/SDSS quasars. II. Type 2 AGN
Short Name:
J/MNRAS/399/1206
Date:
21 Oct 2021
Publisher:
CDS
Description:
This paper is the second part of a work investigating the properties of dusty tori in active galactic nuclei (AGN) by means of multicomponent spectral energy distribution (SED) fitting. It focuses on low-luminosity, low-redshift (z<=0.25) AGN selected among emission line galaxies in the overlapping regions between Spitzer Wide-area Infrared Extragalactic Survey (SWIRE) and Sloan Digital Sky Survey Data Release 4 as well as X-ray, radio and mid-infrared selected type 2 AGN samples from the literature. The available multiband photometry covers the spectral range from the u band up to 160um. Using a standard chi^2^ minimization, the observed SED of each object is fit to a set of multicomponent models comprising a stellar component, a high optical depth (tau_9.7_>=1.0) torus and cold emission from a starburst (SB). The torus components assigned to the majority of the objects were those of the highest optical depth of our grid of models (tau_9.7_=10.0). The contribution of the various components (stars, torus, SB) is reflected in the position of the objects on the Infrared Array Camera (IRAC) colour diagram, with star-, torus- and SB-dominated objects occupying specific areas of the diagrams and composite objects lying in between.
6574. SX Phe
ID:
ivo://CDS.VizieR/J/AJ/106/2493
Title:
SX Phe
Short Name:
J/AJ/106/2493
Date:
21 Oct 2021
Publisher:
CDS
Description:
Simultaneous photometric (uvbyBeta) and spectrographic observations of SX Phe are described. Analysis of the light and velocity frequency spectra are performed. It is shown that all frequencies detected are harmonics or combinations of the fundamental and first harmonic frequencies. Intrinsic (b-y) and c1 values used in conjunction with a model-atmosphere grid appropriate for a star with [M/H]=-1.0 yields <Teff>=7360K and <logg>=3.90. Standard evolutionary models indicate the mass is 1.13 M_{sun}_ and <Mv> value is +2.9. The radial-velocity data indicate a mean radial velocity of -37km/s and a total range of 38km/s.
6575. SX Phe stars in Fornax. II.
ID:
ivo://CDS.VizieR/J/ApJ/685/947
Title:
SX Phe stars in Fornax. II.
Short Name:
J/ApJ/685/947
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have carried out an intensive survey of the northern region of the Fornax dwarf spheroidal galaxy with the aim of detecting the galaxy's short-period pulsating stars (P<0.25 days). Observations collected over three consecutive nights with the Wide Field Imager of the 2.2m MPI telescope at ESO allowed us to detect 85 high-amplitude (0.20-1.00mag in B light) variable stars with periods in the range from 0.046 to 0.126 days, similar to SX Phoenicis stars in Galactic metal-poor stellar populations. The plots of the observed periods vs. the B and V magnitudes show a dispersion largely exceeding the observational errors. To disentangle the matter, we separated the first-overtone from the fundamental-mode pulsators and tentatively identified a group of subluminous variables, about 0.35mag fainter than the others. Their nature as either metal-poor intermediate-age stars or stars formed by the merging of close binary systems is discussed. The rich sample of the Fornax variables also led us to reconstruct the period-luminosity relation for short-period pulsating stars. An excellent linear fit, M_V_=-1.83(+/-0.08)-3.65(+/-0.07)logP_F_, was obtained using 153 {delta} Scuti and SX Phoenicis stars in a number of different stellar systems.
6576. SX Phe stars in globular clusters
ID:
ivo://CDS.VizieR/J/MNRAS/419/342
Title:
SX Phe stars in globular clusters
Short Name:
J/MNRAS/419/342
Date:
21 Oct 2021
Publisher:
CDS
Description:
This study is aimed at investigating the period-luminosity relation of SX Phoenicis (SX Phe) pulsators in Galactic globular clusters (GGCs) and Local Group dwarf galaxies. We verify isochrone-fitting distances of 46 GGCs by fitting their main sequences to a carefully chosen set of nearby, unevolved subdwarfs.
6577. SX Phe stars in NGC 5053
ID:
ivo://CDS.VizieR/J/AJ/110/1186
Title:
SX Phe stars in NGC 5053
Short Name:
J/AJ/110/1186
Date:
21 Oct 2021
Publisher:
CDS
Description:
The results of a major search for photometrically variable blue straggler stars (BSs) in the extremely metal-poor globular cluster NGC 5053 are presented. The survey is based on photometry of over 200 CCD frames (BVI passbands) taken on 18 nights between 1985 and 1994. Five of the 16 BSs monitored for variability are identified as SX Phe stars and their photometric characteristics derived. These five stars are among the shortest-period (49<P<57min), lowest luminosity (3.0<~M_V<~3.3mag), smallest amplitude (0.08<~A_V<~0.25mag) SX Phe stars presently known. Their colors and locations in both B and V period-luminosity (P-L) diagrams suggest that four of the stars (blue stragglers 11, 13, 14, and 15 in the Nemec & Cohen 1989 catalog (1989ApJ...336..780N) are fundamental-mode pulsators, while the fifth and bluest star, No. 7, appears to be a first-overtone pulsator. One of the stars, No. 11, exhibits cycle-to-cycle light variations that are consistent with multimode pulsations; however, not enough photometric information is available to derive its secondary pulsation period. Masses for the stars, estimated directly from the general equation of stellar pulsation and relative to the RR Lyrae stars, range from 0.53M_{sun}_ (NC7) to 1.8M_{sun}_ (NC13). The SX Phe stars are used to derive improved P-L-[Fe/H] relations for SX Phe stars, from which a revised distance modulus of (m-M)0=16.06 is obtained for NGC 5053.
6578. Sydney observatory Galactic survey (SOGS)
ID:
ivo://CDS.VizieR/J/A+A/469/1221
Title:
Sydney observatory Galactic survey (SOGS)
Short Name:
J/A+A/469/1221
Date:
21 Oct 2021
Publisher:
CDS
Description:
First Epoch astrometric and radiometric information of a survey in the optical along the Galactic fourth quadrant is archived for further analysis in the time-domain. A photographic survey of 1.9x10^6^ stars down to B-magnitude 14.5+/-0.5 along the galactic meridian l=(330+/-5){deg},-64{deg}<b<-7{deg} and along the galactic equator 272{deg}<l<341{deg},-7{deg}<b<7{deg}, is provided from century old astrographic plates of Sydney Observatory. Stellar candidates to investigate the Galaxy disk kinematics up to a distance of 1kpc from the Sun are tentatively selected. A catalogue of 4.8x10^5^ stars is provided for further investigation of the galactic disk heating by transient spiral wave or by GMC encounter.
6579. Symbiotic stars catalogue
ID:
ivo://CDS.VizieR/J/A+AS/146/407
Title:
Symbiotic stars catalogue
Short Name:
J/A+AS/146/407
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a new catalogue of symbiotic stars. In our list we include 188 symbiotic stars as well as 30 objects suspected of being symbiotic. For each star, we present basic observational material: coordinates, V and K magnitudes, ultraviolet (UV), infrared (IR), X-ray and radio observations. We also list the spectral type of the cool component, the maximum ionization potential observed, references to finding charts, spectra, classifications and recent papers discussing the physical parameters and nature of each object. Moreover, we present the orbital photometric ephemerides and orbital elements of known symbiotic binaries, pulsational periods for symbiotic Miras, Hipparcos parallaxes and information about outbursts and flickering.
6580. Symbiotic stars multi-epoch UBV(RI)c photometry
ID:
ivo://CDS.VizieR/J/BaltA/17/293
Title:
Symbiotic stars multi-epoch UBV(RI)c photometry
Short Name:
J/BaltA/17/293
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a multi-epoch, accurate UBVRcIc photometric catalog of 83 symbiotic stars and related objects, measured while calibrating the Henden and Munari (2000, Cat. <J/A+AS/143/343>, 2001, Cat. <J/A+A/372/145>, 2006, Cat. <J/A+A/458/339>) photometric sequences around them. The vast majority of the observations where collected in the time interval between October 19, 1998 to April 21, 2002 with the 1.0-m Ritchey-Chretien telescope of the U.S. Naval Observatory, Flagstaff Station (Arizona). On average, UBVRcIc data are given on 3.6 epochs for each program star. The overall budget error of the data is usually better than 0.01mag.