Diagnostics for accretion disks around UX Ori stars based on Balmer, Paschen, and Brackett Lines

Тамбовцева, Л. В.; Гринин, В. П.; Rodgers, Bernadette; Козлова, О. В.

doi:10.1134/1.1374640

Cited by 25 publications

(29 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It is possible in principle that additional excess luminosity is produced by viscous heating of an accreting disk. However, the "missing" luminosity (∼20% L ) requires a very high accretion rate (∼10 −6 M yr −1 ), much higher than current estimates in HAeBe stars (Ghandour et al 1994;Tambovtseva et al 2001). Accretion, as shown by Hartmann et al (1993), cannot contribute significantly to the observed SEDs of HAe stars.…”

Section: Sedsmentioning

confidence: 84%

A reconsideration of disk properties in Herbig Ae stars

Natta

Prusti

Neri

et al. 2001

A&A

Self Cite

331

342

View full text Add to dashboard Cite

Abstract. This paper presents state-of-the-art spectral energy distributions (SEDs) of four Herbig Ae stars, based in part on new data in the mid and far-infrared and at millimeter wavelengths. The SEDs are discussed in the context of circumstellar disk models. We show that models of irradiated disks provide a good fit to the observations over the whole range of wavelengths. We offer a possible solution to the long-standing puzzle caused by the excess emission of Herbig Ae stars, where a large fraction of the stellar luminosity is re-radiated between ∼1.25 and 7 µm, with a peak at about 3 µm. We suggest that this general behaviour can be caused by dust evaporation in disks where the gas component is optically thin to the stellar radiation, as expected if the accretion rate is very low. The creation of a puffed-up inner wall of optically thick dust at the dust sublimation radius can account for the near-infrared characteristics of the SEDs. It can also naturally explain the H and K band interferometric observations of AB Aur (Millan-Gabet et al. 2001), which reveal a ring of emission of radius ∼0.3 AU. Finally, irradiated disk models can easily explain the observed intensity of the 10 µm silicate features and their variation from star to star.

show abstract

Section: Sedsmentioning

confidence: 84%

A reconsideration of disk properties in Herbig Ae stars

Natta

Prusti

Neri

et al. 2001

A&A

Self Cite

331

342

View full text Add to dashboard Cite

show abstract

“…Using a non-LTE analysis of the line optical depths, they showed that the infalling gas cannot be heavily hydrogen depleted, which suggests a similarity between HAEs and classical T Tauri stars, where gas infall occurs in an analogous fashion. Estimates of the accretion rates for HAEs obtained by modeling the line profiles have been made, for example, by Tambovtseva et al (2001), Muzerolle et al (2004), andMendigutia et al (2011).…”

Section: Hybrid Model: Disk Wind X-wind and Magnetospherementioning

confidence: 99%

“…The gas electron temperature T e is assumed to be constant and equal to 10 000 K in all models except B5 and B6; in the latter models T e = 8000 K. The choice of the disk wind parameters is conditioned by the results of the magneto-centrifugal disk wind model for TTSs with some changes in the launching region because of the difference in the inner accretion disk structure (e.g., Natta et al 2001;Dullemond et al 2001). The range of the mass-loss values is based on the estimates of mass loss and accretion rates from the literature (e.g., Hillenbrand et al 1992;Lada & Adams 1992;Hartmann et al 1993;Tambovtseva et al 2001;Muzerolle et al 2004;Garcia Lopez et al 2006;Donehew & Brittain 2011;Klaassen et al 2013;Mendigutía et al 2013).…”

Section: Disk Wind Modelmentioning

confidence: 99%

“…We calculated the excitation and ionization states of the atoms using our codes developed by Grinin & Katysheva (1980), Grinin & Mitskevich (1990), and Tambovtseva et al (2001) for media with steep velocity gradients. The radiation terms in the stationarity equations corresponding to transitions between discrete levels were taken into account in the Sobolev approximation (SA) (Sobolev 1960).…”

Section: Disk Wind Modelmentioning

confidence: 99%

“…Several teams have modeled the hydrogen line profiles or interferometric observables of T Tauri stars (TTSs) or Herbig Ae/Be stars (HAEBEs) (e.g., Muzerolle et al 2001;Kurosawa et al 2006Kurosawa et al , 2011Lima et al 2010;Proga et al 1998;Tambovtseva et al 2001;Muzerolle et al 2004;RousseletPerraut et al 2010;Weigelt et al 2011;Lumsden et al 2012). It is difficult to investigate the structure of the emitting region in hot young stars because this region usually consists of several components.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Hydrogen lines as a diagnostic tool for studying multicomponent emitting regions in hot young stars: magnetosphere, X-wind, and disk wind

Тамбовцева

Гринин

Weigelt

2014

A&A

Self Cite

View full text Add to dashboard Cite

Infrared interferometric observations with high spatial and spectral resolution and their quantitative modeling provide us with a unique opportunity to improve our understanding of the circumstellar environment of young stars and the accretion-ejection process. The goal of this paper is to investigate various models of the emitting regions in young Herbig Ae/Be stars that consist of (i) a compact rotating magnetosphere; (ii) an X-wind; and (iii) a disk wind. These models can be used, for example, to quantitatively interpret line profile measurements and infrared interferometric observations with the AMBER instrument of the Very Large Telescope Interferometer (VLTI) in the high spectral resolution mode (R = 12 000). VLTI/AMBER observations allow us to resolve the disk wind region and study the flux contribution of the unresolved magnetosphere and X-wind region to the total line flux. Analyzing the results of our non-LTE calculations, we conclude that the mechanisms of the different broadening of emission lines of different series include (1) the kinematic expansion due to the motion of the outflowing, accelerating gas in the magneto-centrifugal disk wind; (2) the Stark effect; and (3) the rotation of the magnetosphere. We also investigated extinction effects that can influence the shape of the line profiles. We considered the obscuration of the outer disk wind by an opaque dust and gas disk, the obscuration of the disk wind by a flared disk or by dust in the disk wind itself, and absorption of the star and disk continuum radiation in the disk wind along the line of sight. We show that due to extinction effects, the line profiles can change from double-peaked to single-peaked and P Cygni profiles. We studied the contribution of the different components of the stellar environment to different hydrogen emission lines and investigated how this contribution is dependent on the model parameters. The results of this study can be used for the detailed modeling of the emitting regions of individual young stars.

show abstract

The Tabby Cat in the Picture Puzzle: Fitting Unusual Stars into Scenarios of Stellar Evolution

Trimble

2003

Highlights of Spanish Astrophysics III

View full text Add to dashboard Cite

Diagnostics for accretion disks around UX Ori stars based on Balmer, Paschen, and Brackett Lines

Cited by 25 publications

References 20 publications

A reconsideration of disk properties in Herbig Ae stars

A reconsideration of disk properties in Herbig Ae stars

Hydrogen lines as a diagnostic tool for studying multicomponent emitting regions in hot young stars: magnetosphere, X-wind, and disk wind

The Tabby Cat in the Picture Puzzle: Fitting Unusual Stars into Scenarios of Stellar Evolution

Contact Info

Product

Resources

About