Probing T Tauri Accretion and Outflow with 1 Micron Spectroscopy

  title={Probing T Tauri Accretion and Outflow with 1 Micron Spectroscopy},
  author={Suzan Edwards and William J. Fischer and L. A. Hillenbrand and John Kwan},
  journal={The Astrophysical Journal},
In a high-dispersion 1 μm survey of 39 classical T Tauri stars (CTTSs) veiling is detected in 80% of the stars, and He I λ10830 and Pγ line emission in 97%. On average, the 1 μm veiling exceeds the level expected from previously identified sources of excess emission, suggesting the presence of an additional contributor to accretion luminosity in the star-disk interface region. Strengths of both lines correlate with veiling, and at Pγ there is a systematic progression in profile morphology with… 
Redshifted Absorption at He I λ10830 as a Probe of the Accretion Geometry of T Tauri Stars
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Modeling T Tauri Winds from He I λ10830 Profiles
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Tracing the origins of permitted emission lines in RU Lupi down to AU scales
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Where are the hot ion lines in classical T Tauri stars formed
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The Evolution of Protoplanetary Disks: Probing the Inner Disk of Very Low Accretors
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Structure and dynamics of the accretion process and wind in TW Hya
Time-domain spectroscopy of the classical accreting T Tauri star, TW Hya, covering a decade and spanning the far UV to the near-infrared spectral regions can identify the radiation sources, the


He I λ10830 as a Probe of Winds in Accreting Young Stars
He I λ10830 profiles acquired with Keck's NIRSPEC for six young low-mass stars with high disk accretion rates (AS 353A, DG Tau, DL Tau, DR Tau, HL Tau, and SVS 13) provide new insight into
Emission-Line Diagnostics of T Tauri Magnetospheric Accretion. I. Line Profile Observations
We present high-resolution spectra of classical T Tauri stars in Taurus in the range 5800–9000 A to critically examine the current theories of magnetospheric accretion. In this paper, we focus on the
A Hot Wind from the Classical T Tauri Stars: TW Hydrae and T Tauri
Spectroscopy of the infrared He I (10830 A) line with NIRSPEC on Keck and CSHELL at the IRTF, and of the ultraviolet C III (977 A) and O VI (1032 A) emission with FUSE, reveals that the classical T
The Loopy Ultraviolet Line Profiles of RU Lupi: Accretion, Outflows, and Fluorescence
We present far-ultraviolet (FUV) spectra of the classical T Tauri star RU Lup covering the 912–1710 A spectral range, as observed by the Hubble Space Telescope STIS and the Far Ultraviolet
The Structure and Emission of the Accretion Shock in T Tauri Stars
We have examined one of the key predictions of the magnetospheric infall model for classical T Tauri stars (CTTS), namely, the formation of a shock on the stellar surface. We find that accretion
Helium Emission from Classical T Tauri Stars: Dual Origin in Magnetospheric Infall and Hot Wind
High-resolution emission-line profiles of He I and He II in 31 classical T Tauri stars are analyzed with the aim of probing the environs of the star-disk interface in accreting low-mass young stars.
Profiles of Strong Permitted Lines in Classical T Tauri Stars
We present a spectral analysis of 30 T Tauri stars observed with the Hamilton echelle spectrograph over more than a decade. One goal is to test magnetospheric accretion model predictions.
Variability of Southern T Tauri Stars. II. The Spectral Variability of the Classical T Tauri Star TW Hydrae
We present the analysis of 42 spectra of the Classical T Tauri star TW Hya observed with the FEROS echelle spectrograph over 2 yr. We determined the rotational and radial velocities of TW Hya,
The Narrow Emission Lines of T Tauri Stars
We present the first comprehensive study of the narrow emission lines of T Tauri stars (TTS). These narrow lines have been reported in the literature as originating in the stellar atmosphere and
Hamilton echelle spectra of young stars. I: Optical veiling
An extensive set of veiling measurements of T Tauri stars covering almost the entire optical spectrum is presented. These are based on Hamilton echelle spectra obtained during 1987-1989. A full range