Line formation in the inner winds of classical T Tauri stars: testing the conical-shell wind solution

Abstract

We present the emission line profile models of hydrogen and helium based on the results from axisymmetric magnetohydrodynamics (MHD) simulations of the wind formed near the disk-magnetosphere boundary of classical T Tauri stars (CTTSs). We extend the previous outflow models of `the conical-shell wind' by Romanova et al. to include a well defined magnetospheric accretion funnel flow which is essential for modelling the optical and near-infrared hydrogen and helium lines of CTTSs. The MHD model with an intermediate mass-accretion rate shows outflows in conical-shell shape with a half opening angle about 35 degrees. The flow properties such as the maximum outflow speed in the conical-shell wind, maximum inflow speed in the accretion funnel, mass-accretion and mass-loss rates are comparable to those found in a typical CTTS. The density, velocity and modified temperature from the MHD simulations are used in a separate radiative transfer model to predict the line profiles and test the consistency of the MHD models with observations. The line profiles are computed with various combinations of X-ray luminosities, temperatures of X-ray emitting plasma, and inclination angles. A rich diversity of line profile morphology is found, and many of the model profiles are very similar to those found in observations. We find that the conical-shell wind may contribute to the emission in some hydrogen lines (e.g. H-alpha, H-beta, Pa-beta and Pa-gamma) significantly when the temperature in the wind is relatively high (e.g. \sim 10^{4} K); however, the wind contribution decreases rapidly when a lower wind temperature is adopted. The model well reproduces a relatively narrow and low-velocity blueshifted absorption component in He I (10830), which are often seen in observations.

16 pages, 10 figures, accepted for publication in MNRAS

References in corpus (15)

• Which jet launching mechanism(s) in TTauri stars?
• Probing T Tauri Accretion and Outflow with 1 Micron Spectroscopy
• On the formation of H-alpha line emission around classical T Tauri stars
• Magnetospheric accretion on the T Tauri star BP Tauri
• Magnetic fields and accretion flows on the classical T Tauri star V2129 Oph
• Accretion-Powered Stellar Winds II: Numerical Solutions for Stellar Wind Torques
• "Propeller" Regime of Disk Accretion to Rapidly Rotating Stars
• Modeling T Tauri Winds from He I 10830 Profiles
• The X-ray soft excess in classical T Tauri stars
• X-ray emission from dense plasma in CTTSs: Hydrodynamic modeling of the accretion shock
• High Resolution X-ray Spectroscopy of T Tauri Stars in the Taurus-Auriga Complex
• T Tauri stellar magnetic fields: He I measurements
• Oscillations of MHD shock waves on the surfaces of T Tauri stars
• Emission-line profile modelling of structured T Tauri magnetospheres
• Tracing the origins of permitted emission lines in RU Lupi down to AU scales

Cited by in corpus (32)

• Kinematic links and the co-evolution of MHD winds, jets, and inner disks from a high-resolution optical [OI] survey
• Spectral variability of classical T Tauri stars accreting in an unstable regime
• X-Shooter spectroscopy of young stellar objects: V - Slow winds in T Tauri stars
• Accretion, Outflows, and Winds of Magnetized Stars
• Diagnosing Mass Flows Around Herbig Ae/Be Stars Using the He I 10830 Line
• Highly Variable Extinction and Accretion in the Jet-driving Class I Type Young Star PTF 10nvg (V2492 Cyg, IRAS 20496+4354)
• Inner disk structure of the classical T Tauri star LkCa 15
• On the origin of the correlations between the accretion luminosity and emission line luminosities in pre-main sequence stars
• Accreting protoplanets: Spectral signatures and magnitude of gas and dust extinction at H alpha
• Probing the wind launching regions of the Herbig Be star HD 58647 with high spectral resolution interferometry
• Probing the magnetospheric accretion region of the young pre-transitional disk system DoAr 44 using VLTI/GRAVITY
• Interpreting Near Infrared Hydrogen Line Ratios in T Tauri Stars
• Rotational evolution of solar-type protostars during the star-disk interaction phase
• Stable and Unstable Regimes of Mass Accretion onto RW Aur A
• PTF 14jg: The Remarkable Outburst and Post-Burst Evolution of a Previously Anonymous Galactic Star
• Structure and Dynamics of the Accretion Process and Wind in TW Hya
• X-Shooter spectroscopy of young stellar objects - VI - HI line decrements
• Hydrogen Emission from Accretion and Outflow in T Tauri Stars
• Dynamics of wind and the dusty environments in the accreting T Tauri stars RY Tau and SU Aur
• The He I $\lambda$10830 $\mathring{A}$ line as a probe of winds and accretion in young stars in Lupus and Upper Scorpius
• A non-LTE modeling of narrow emission components of He and Ca lines in optical spectra of CTTS
• A High-Resolution Multiband Survey of Westerlund 2 With the Hubble Space Telescope. II. Mass accretion in the Pre-Main Sequence Population
• MHD Simulations of Magnetospheric Accretion, Ejection and Plasma-field Interaction
• The role of magnetic fields in pre-main sequence stars
• Wind Dynamics and Circumstellar Extinction Variations in the T Tauri Star RY Tau
• Possible progression of mass flow processes around young intermediate-mass stars based on high-resolution near-infrared spectroscopy. I. Taurus
• Episodic High Velocity Outflows from V899 Mon: A Constraint On The Outflow Mechanisms
• Density streams in the disc winds of Classical T Tauri stars
• Evidence of a Disk-wind Origin for Fluorescent H${}_2$ in Classical T Tauri Stars
• Forbidden Emission Line spectro-imaging of the RU Lupi jet and Low Velocity Component
• Magnetospheric Accretions and the Inner Winds of Classical T Tauri Stars
• Spectral line fluorescence in moving envelopes of stars