- ID:
- ivo://CDS.VizieR/J/A+A/631/A53
- Title:
- 1-D optical spectra for IRAS19135+3937
- Short Name:
- J/A+A/631/A53
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We aim to determine the geometry, density gradient, and velocity structure of jets in post-asymptotic giant branch (post-AGB) binaries. Our high cadence time series of high-resolution optical spectra of jet-creating post-AGB binary systems provide us with a unique tomography of the jet. We determine the spatio-kinematic structure of the jets based on these data by fitting the synthetic spectral line profiles created by our model to the observed, orbital phase-resolved, H{alpha}-line profiles of these systems. The fitting routine is provided with an initial spectrum and is allowed to test three configurations, derived from three specific jet launching models: a stellar jet launched by the star, an X-wind, and a disk wind configuration. We apply a Markov-chain Monte Carlo routine in order to fit our model to the observations. Our fitting code is tested on the post-AGB binary IRAS19135+3937. We find that a model using the stellar jet configuration gives a marginally better fit to our observations. The jet has a wide half-opening angle of about 76 degrees and reaches velocities up to 870km/s. Our methodology is successful in determining some parameters for jets in post-AGB binaries. The model for IRAS19135+3937 includes a transparent, low density inner region (for a half-opening angle <40{deg}). The source feeding the accretion disk around the companion is most likely the circumbinary disk. We will apply this jet fitting routine to other jet-creating post-AGB stars in order to provide a more complete description of these objects. We aim at describing and understanding binary interaction processes in systems with very evolved companions. Here, we focus on understanding the origin and determining the properties of the high-velocity outflow observed in one such system.
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5062. 30 Dor
- ID:
- ivo://CDS.VizieR/J/ApJ/413/604
- Title:
- 30 Dor
- Short Name:
- J/ApJ/413/604
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- (no description available)
- ID:
- ivo://CDS.VizieR/II/187A
- Title:
- 30 Doradus OB Associations
- Short Name:
- II/187A
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Johnson UBV photometry is presented for 2395 stars in the OB associations of 30 Doradus in the Large Magellanic Cloud. The CCD fields cover an area of 50 square arcminutes in the central region. The entire catalog (exclusive of the dense core cluster R136) is photometrically complete to V=B=18mag and U=17mag, although the completeness magnitudes are fainter for regions with less nebular contamination.
- ID:
- ivo://CDS.VizieR/J/A+A/624/A129
- Title:
- 30 Dor red supergiant stars radial velocities
- Short Name:
- J/A+A/624/A129
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The incidence of multiplicity in cool, luminous massive stars is relatively unknown compared to their hotter counterparts.Here we present radial velocity (RV) measurements and investigate the multiplicity properties of red supergiants (RSGs) in the 30~Doradus region of the Large Magellanic Cloud using multi-epoch visible spectroscopy from the VLT-FLAMES Tarantula Survey. Exploiting the high density of absorption features in visible spectra of cool stars, we use a novel slicing technique to estimate RVs of 17 candidate RSGs in 30 Doradus from cross-correlation of the observations with model spectra. We provide absolute RV measurements (precise to better than +/-1km/s) for our sample and estimate line-of-sight velocities for the Hodge 301 and SL 639 clusters, which agree well with those of hot stars in the same clusters. By combining results for the RSGs with those for nearby B-type stars, we estimate systemic velocities and line-of-sight velocity dispersions for the two clusters, obtaining estimates for their dynamical masses of log(M_dyn_/M_{sun}_)=~3.8+/-0.3 for Hodge 301, and an upper limit of log(M_dyn_/M_{sun}_)<~3.1+/-0.8 for SL 639, assuming Virial equilibrium. Analysis of the multi-epoch data reveals one RV-variable, potential binary candidate (VFTS 744), which is likely a semi-regular variable asymptotic giant branch star. Calculations of semi-amplitude velocities for a range of RSGs in model binary systems and literature examples of binary RSGs were used to guide our RV variability criteria. We estimate an upper limit on the observed binary fraction for our sample of 0.3, where we are sensitive to maximum periods for individual objects in the range of 1 to 10000-days and mass-ratios above 0.3 depending on the data quality. From simulations of the RV measurements from binary systems given the current data we conclude that systems within the parameter range q>0.3, logP[days]<3.5, would be detected by our variability criteria, at the 90% confidence level. The intrinsic binary fraction, accounting for observational biases, is estimated using simulations of binary systems with an empirically defined distribution of parameters where orbital periods are uniformly distributed in the 3.3<logP[days]<4.3 range. A range of intrinsic binary fractions are considered; a binary fraction of 0.3 is found to best reproduce the observed data. We demonstrate that RSGs are effective extragalactic kinematic tracers by estimating the kinematic properties, including the dynamical masses of two LMC young massive clusters. In the context of binary evolution models, we conclude that the large majority of our sample consists of currently effectively single stars (either single or in long period systems). Further observations at greater spectral resolution and/or over a longer baseline are required to search for such systems.
- ID:
- ivo://CDS.VizieR/J/ApJ/836/115
- Title:
- Double-component model fitting of elliptical gal.
- Short Name:
- J/ApJ/836/115
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigate two-dimensional image decomposition of nearby, morphologically selected early-type galaxies (ETGs). We are motivated by recent observational evidence of significant size growth of quiescent galaxies and theoretical development advocating a two-phase formation scenario for ETGs. We find that a significant fraction of nearby ETGs show changes in isophotal shape that require multi-component models. The characteristic sizes of the inner and outer component are ~3 and ~15kpc. The inner component lies on the mass-size relation of ETGs at z~0.25-0.75, while the outer component tends to be more elliptical and hints at a stochastic buildup process. We find real physical differences between single- and double-component ETGs, with double-component galaxies being younger and more metal-rich. The fraction of double-component ETGs increases with increasing {sigma} and decreases in denser environments. We hypothesize that double-component systems were able to accrete gas and small galaxies until later times, boosting their central densities, building up their outer parts, and lowering their typical central ages. In contrast, the oldest galaxies, perhaps due to residing in richer environments, have no remaining hints of their last accretion episode.
- ID:
- ivo://CDS.VizieR/VII/168
- Title:
- Double Galaxies in SGP region
- Short Name:
- VII/168
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- 630 double systems of galaxies brighter than about 17mag(B) were found by examining 100 glass copies of ESO(B) survey plates, covering the Southern Galactic Cap (GLAT<-50deg, DE<-27deg). The selection criteria are similar to those defined by Zonn (1962). The measuring, reduction and error analysis parameters have been described by Zou et al. (1984).
- ID:
- ivo://CDS.VizieR/J/MNRAS/492/2709
- Title:
- Double-lined spectroscopic binaries catalog
- Short Name:
- J/MNRAS/492/2709
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The study of a selected set of 69 double-lined spectroscopic binaries (SB2) with well defined visual and spectroscopic orbits was carried out. The orbital parallax, the mass, the colour, and the luminosity of each component were derived from observational data for almost all of these systems. We have also obtained an independent estimation of the component masses by comparing the colour-luminosity diagram (CMD) to the stellar evolution tracks reported by Pietrinferni. Nearly all of the observational points on the CMD are located between two tracks of slightly different mass or which fall very close to the one corresponding to a unique mass value. The masses obtained from the stellar model are in good agreement with their empirical values determined by parallax techniques (orbital, dynamical, and Gaia). This means that our adopted model is rather reliable and can therefore be used to infer further information, such as the age of each component in the studied systems. Our results indicate a fair correspondence between the age of primaries and secondary stars within 3{sigma}. Nevertheless, we caution that these age indications suffer of uncertainties due to both inhomogeneities/low precision of the adopted photometric data and possible systematics. Finally, it is statistically shown that along with the orbital and trigonometric parallaxes, the dynamical parallax can serve as a reliable tool for distance estimates.
- ID:
- ivo://CDS.VizieR/J/MNRAS/510/1515
- Title:
- Double-lined spectroscopic binaries in M11
- Short Name:
- J/MNRAS/510/1515
- Date:
- 10 Jan 2022 09:23:04
- Publisher:
- CDS
- Description:
- We have developed a new method for spectral analysis of binaries. Our method successfully identifiesSB2 candidates from high-resolution Gaia-ESO spectra. Compared to the commonly used cross-correlation function analysis, it works for binaries with rapidly rotating components. We test our method on synthetic and observational spectra of BAFG-stars with vsin(i) from 1 to 330km/s in the open cluster M11. We confirm five previously detected SB2 candidates and find 19 new ones. For three SB2 candidates we find circular orbits and obtain dynamical mass ratios.
- ID:
- ivo://CDS.VizieR/J/AJ/131/666
- Title:
- Double-lobed radio quasars from the SDSS
- Short Name:
- J/AJ/131/666
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have combined a sample of 44,984 quasars selected from the Sloan Digital Sky Survey (SDSS) Data Release 3 (Cat. <II/259>) with the FIRST radio survey (Cat. <VIII/71>). Using a novel technique in which the optical quasar position is matched to the complete radio environment within 450", we are able to characterize the radio morphological make-up of what is essentially an optically selected quasar sample, regardless of whether the quasar (nucleus) itself has been detected in the radio.
- ID:
- ivo://CDS.VizieR/J/MNRAS/446/2985
- Title:
- Double-lobed radio sources catalog
- Short Name:
- J/MNRAS/446/2985
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Current wide-area radio surveys are dominated by active galactic nuclei, yet many of these sources have no identified optical counterparts. Here we investigate whether one can constrain the nature and properties of these sources, using Fanaroff-Riley type II (FR II) radio galaxies as probes. These sources are easy to identify since the angular separation of their lobes remains almost constant at some tens of arcseconds for z>1. Using a simple algorithm applied to the Faint Images of the Radio Sky at Twenty-cm survey, we obtain the largest FR II sample to date, containing over 104 double-lobed sources. A subset of 459 sources is matched to Sloan Digital Sky Survey quasars. This sample yields a statistically meaningful description of the fraction of quasars with lobes as a function of redshift and luminosity. This relation is combined with the bolometric quasar luminosity function and a disc-lobe correlation to obtain a robust prediction for the density of FR IIs on the radio sky. We find that the observed density can be explained by the population of known quasars, implying that the majority of powerful jets originate from a radiatively efficient accretion flow with a linear jet-disc coupling. Finally, we show that high-redshift jets are more often quenched within 100kpc, suggesting a higher efficiency of jet-induced feedback into their host galaxies.