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641. Echelle spectroscopy of {delta} Vel
ID:
ivo://CDS.VizieR/J/A+A/528/A21
Title:
Echelle spectroscopy of {delta} Vel
Short Name:
J/A+A/528/A21
Date:
21 Oct 2021
Publisher:
CDS
Description:
The nearby multiple system delta Velorum contains a widely detached eclipsing binary and a third component. We take advantage of this system offering the opportunity to determine the set of fundamental parameters (masses, luminosities, and radii) of three coeval stars with sufficient precision to test models of stellar evolution. Extensive high-resolution spectroscopy is analyzed by the broadening function technique to provide the first spectroscopic orbit of the eclipsing pair. Simultaneous analysis of the spectroscopic data and the SMEI satellite light curve is performed to provide astrophysical parameters for the components. We use a modified Roche model assuming an eccentric orbit and asynchronous rotation. The observations show that components of the eclipsing pair rotate at about two-thirds of the break-up velocity, which excludes any chemical peculiarity and results in a non-uniform surface brightness. Although the inner orbit is eccentric, no apsidal motion is seen during the SMEI photometric observations. For the inner orbit, the orbital parameters are eccentricity e=0.290, longitude of the periastron passage omega=109{deg}, and inclination 89.0{deg}. The component masses of M(Aa)=2.53+/-0.11M_{sun}_, M(Ab)=2.37+/-0.10M_{sun}_, and M(B)~1.5M_{sun}_ combined with the inferred radii of the Aa and Ab components indicate that the eclipsing pair has already left the main sequence and that the estimated age of the system is about 400Myr.
642. Eclipsing binaries in NGC6791
ID:
ivo://CDS.VizieR/J/A+A/525/A2
Title:
Eclipsing binaries in NGC6791
Short Name:
J/A+A/525/A2
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present photometric and spectroscopic observations of eclipsing binaries and single stars, which are members of the open cluster NGC6791. These were used to measure precise and accurate masses, radii and metallicity of the stars along with reddening and distance modulus to the cluster.
643. EDD: All Digital HI profile catalog
ID:
ivo://CDS.VizieR/J/AJ/138/1938
Title:
EDD: All Digital HI profile catalog
Short Name:
J/AJ/138/1938
Date:
21 Oct 2021
Publisher:
CDS
Description:
An important component of the Extragalactic Distance Database is a group of catalogs related to the measurement of HI line profile parameters. One of these is the All Digital HI catalog which contains an amalgam of information from new data and old. The new data result from observations with Arecibo and Parkes Telescopes and with the Green Bank Telescope, including continuing input since the award of the NRAO Cosmic Flows Large Program. The old data have been collected from archives, wherever available, particularly the Cornell University Digital HI Archive, the Nancay Telescope extragalactic HI archive, and the Australia Telescope HI archive. The catalog currently contains information on ~15000 profiles relating to ~13000 galaxies. The channel-flux per channel files, from whatever source, is carried through a common pipeline. The derived parameter of greatest interest is W_m50_, the profile width at 50% of the mean flux. After appropriate adjustment, the parameter W_mx_ is derived, the line width that statistically approximates the peak-to-peak maximum rotation velocity before correction for inclination, 2V_max_sini.
644. EELGs out to z~1 in zCOSMOS
ID:
ivo://CDS.VizieR/J/A+A/578/A105
Title:
EELGs out to z~1 in zCOSMOS
Short Name:
J/A+A/578/A105
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present line measurements and physical properties of a sample of 165 extreme emission-line galaxies (EELGs) in the zCOSMOS 20k-Bright Survey (Lilly et al., 2009, Cat. J/ApJS/184/218). The zCOSMOS spectra consist of ~1h integrations in the medium resolution LRRED grism setting (R~600 with 2.5{AA}/pixel), covering a wavelength range 5550<{lambda}<9650{AA}. Measured emission-line fluxes are given in units of 10^-17^erg/s/cm^2^. Flux errors have been derived following Perez-Montero et al. (2013A&A...549A..25P) and Amorin et al. (2012ApJ...749..185A and 2012ApJ...754L..22A). No extinction correction has been applied to these fluxes. For each galaxy the reddening constant, c(H{beta}), is presented. These values and their corresponding uncertainties have been derived from the H{alpha}/H{beta} or H{gamma}/H{beta} ratios, whenever possible. A reddening constant derived from the SED best-fitting was adopted for (a) those galaxies where the computation of c(H{beta}) from emission lines is not possible because of the lack of lines, or (b) the corresponding line ratio produces a negative extinction correction (i.e., Ha/Hb<2.82 or Hg/Hb<0.47, assuming Case B recombination with T_e_=2*10^4K, n_e_=100cm^-3^). Stellar mass and 1{sigma} uncertainties have been obtained from SED fitting (Bolzonella et al., 2010A&A...524A..76B) after removal of the flux contribution from strong emission lines.
645. EFAR Catalog. VII.
ID:
ivo://CDS.VizieR/J/MNRAS/321/277
Title:
EFAR Catalog. VII.
Short Name:
J/MNRAS/321/277
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present peculiar velocities for 85 clusters of galaxies in two large volumes at distances between 6000 and 15000km/s in the directions of Hercules-Corona Borealis and Perseus-Pisces-Cetus (the EFAR sample). These velocities are based on Fundamental Plane (FP) distance estimates for early-type galaxies in each cluster. We fit the FP using a maximum likelihood algorithm which accounts for both selection effects and measurement errors, and yields FP parameters with smaller bias and variance than other fitting procedures. We obtain a best-fitting FP with coefficients consistent with the best existing determinations. We measure the bulk motions of the sample volumes using the 50 clusters with the best-determined peculiar velocities.
646. EFAR cluster and galaxy selection
ID:
ivo://CDS.VizieR/J/ApJS/106/1
Title:
EFAR cluster and galaxy selection
Short Name:
J/ApJS/106/1
Date:
21 Oct 2021
Publisher:
CDS
Description:
The EFAR project is a study of 736 candidate elliptical galaxies in 84 clusters lying in two regions, toward Hercules-Corona Borealis and Perseus-Pisces-Cetus, at distances cz~6000-15000km/s. In this paper (the first of a series), we present an introduction to the EFAR project and describe in detail the selection of the clusters and galaxies in our sample. Fundamental data for the galaxies and clusters are given, including accurate new positions for each galaxy and redshifts for each cluster. The galaxy selection functions are determined by using diameters measured from Schmidt sky survey images for 2185 galaxies in the cluster fields. Future papers in this series will present the spectroscopic and photometric observations of this sample, investigate the properties of the fundamental plane for elliptical galaxies, and determine the large-scale peculiar velocity fields in these two regions of the universe.
647. EFAR galaxies redshifts & velocity dispersions
ID:
ivo://CDS.VizieR/J/MNRAS/305/259
Title:
EFAR galaxies redshifts & velocity dispersions
Short Name:
J/MNRAS/305/259
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the spectroscopic data for the galaxies studied in the EFAR project, which is designed to measure the properties and peculiar motions of early-type galaxies in two distant regions. We have obtained 1319 spectra of 714 early-type galaxies over 33 observing runs on 10 different telescopes. We describe the observations and data reductions used to measure redshifts, velocity dispersions and the Mgb and Mg_2_ Lick linestrength indices. Detailed simulations and intercomparison of the large number of repeat observations lead to reliable error estimates for all quantities. The measurements from different observing runs are calibrated to a common zero-point or scale before being combined, yielding a total of 706 redshifts, 676 velocity dispersions, 676 Mgb linestrengths and 582 Mg_2_ linestrengths. The median estimated errors in the combined measurements are {Delta}cz=20km/s, {Delta}sigma/sigma=9.1%, {Delta}Mgb/Mgb=7.2% and {Delta}Mg_2_=0.015mag. Comparison of our measurements with published data sets shows no systematic errors in the redshifts or velocity dispersions, and only small zero-point corrections to bring our linestrengths on to the standard Lick system. We have assigned galaxies to physical clusters by examining the line-of-sight velocity distributions based on EFAR and ZCAT redshifts, together with the projected distributions on the sky. We derive mean redshifts and velocity dispersions for these clusters, which will be used in estimating distances and peculiar velocities and to test for trends in the galaxy population with cluster mass. The spectroscopic parameters presented here for 706 galaxies combine high-quality data, uniform reduction and measurement procedures, and detailed error analysis. They form the largest single set of velocity dispersions and linestrengths for early-type galaxies published to date.
648. EFAR photometric data
ID:
ivo://CDS.VizieR/J/MNRAS/292/499
Title:
EFAR photometric data
Short Name:
J/MNRAS/292/499
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present R-band CCD photometry for 776 galaxies observed in the EFAR (Elliptical FAR away) project. The photometry is compared with photoelectric data, showing that a common zero-point good to better than 1% and a precision of 0.03mag per zero-point have been achieved. We give the circularly averaged surface brightness profiles and the photometric parameters of the 762 program galaxies, D(n) diameters (at 20.5mag/arcsec^2^), half-luminosity radii Re, total magnitudes m_T_, and average effective surface brightnesses <SBe>. More than 80% of the profiles have a global S/N ratio larger than 300. The extrapolation needed to derive total magnitudes is less than 10% for 80% of the fits. More than 80% of the galaxies have mean effective surface brightness larger than the observed sky brightness. In 90% of the profiles the estimate of the contamination of the sky by the galaxy light is less than 1%. We derive total magnitudes and half-luminosity radii to better than 0.15mag and 25%, respectively, for 90% of our sample. In contrast, external comparisons show that data in the literature can be strongly affected by systematic errors due to large extrapolations, small radial range, sky subtraction errors, seeing effects, and the use of a simple R^1/4^ fit. The resulting errors can easily amount to more than 0.5mag in the total magnitudes and 50% in the half-luminosity radii.
649. Effective temperatures of low-mass stars
ID:
ivo://CDS.VizieR/J/ApJ/879/105
Title:
Effective temperatures of low-mass stars
Short Name:
J/ApJ/879/105
Date:
21 Oct 2021
Publisher:
CDS
Description:
High-resolution, near-infrared spectra will be the primary tool for finding and characterizing Earth-like planets around low-mass stars. Yet, the properties of exoplanets cannot be precisely determined without accurate and precise measurements of the host star. Spectra obtained with the Immersion Grating Infrared Spectrometer simultaneously provide diagnostics for most stellar parameters, but the first step in any analysis is the determination of the effective temperature. Here we report the calibration of high-resolution H-band spectra to accurately determine the effective temperature for stars between 4000 and 3000K (~K8-M5) using absorption line-depths of FeI, OH, and Al I. The field star sample used here contains 254 K and M stars with temperatures derived using BT-Settl synthetic spectra. We use 106 stars with precise temperatures in the literature to calibrate our method, with typical errors of about 140K, and systematic uncertainties less than ~120K. For the broadest applicability, we present Teff-line-depth-ratio relationships, which we test on 12 members of the TW Hydrae Association and at spectral resolving powers between ~10000 and 120000. These ratios offer a simple but accurate measure of effective temperatures in cool stars that are distance and reddening independent.
650. EG And Halpha line fluxes and radial velocities
ID:
ivo://CDS.VizieR/J/A+A/646/A116
Title:
EG And Halpha line fluxes and radial velocities
Short Name:
J/A+A/646/A116
Date:
21 Oct 2021
Publisher:
CDS
Description:
Structure of the wind from the cool giants in symbiotic binaries carries important information for understanding the wind mass transfer to their white dwarf companions, its fuelling, and thus the path to different phases of symbiotic-star evolution. In this paper we indicate a non-spherical distribution of the neutral wind zone around the red giant (RG) in the symbiotic binary star EG And. In particular, its focusing towards the orbital plane and the asymmetry alongside the orbital motion of the RG. We achieved this aim by analysing the periodic orbital variations of fluxes and radial velocities of individual components of the H_alpha and [OIII] lambda 5007 lines observed on our high-cadence medium (R~11000) and high-resolution (R~38000) spectra. The asymmetric shaping of the neutral wind zone at the near-orbital-plane region is indicated by: (i) the asymmetric course of the Halpha core emission fluxes along the orbit, (ii) the presence of their secondary maximum around the orbital phase phi=0.1 possibly caused by the refraction effect, and (iii) the properties of the H_alpha broad wing emission originating by Raman scattering on H^0^ atoms. The wind is substantially compressed from polar directions to the orbital plane as constrained by the location of the [OIII] lambda 5007 line emission zones in the vicinity of the RG at/around its poles. The corresponding mass-loss rate from the polar regions of <~10^-8^M_{sun}_/yr is a factor of >~10 lower than the average rate of ~10^-7^M_{sun}_/yr derived from nebular emission of the ionized wind from the RG, and it is two orders of magnitude lower than that measured in the near-orbital-plane region from Rayleigh scattering. The startling properties of the nebular [OIII] lambda 5007 line in EG And provides an independent indication of the wind focusing towards the orbital plane -- the key to understanding the efficient wind mass transfer in symbiotic binary stars.

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