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Articles 1 - 4 of 4
Full-Text Articles in Physical Sciences and Mathematics
Kinematic Links And The Coevolution Of Mhd Winds, Jets, And Inner Disks From A High-Resolution Optical [Oi] Survey, Andrea Banzatti, Ilaria Pascucci, Suzan Edwards, Min Fang, Uma Gorti, Mario Flock
Kinematic Links And The Coevolution Of Mhd Winds, Jets, And Inner Disks From A High-Resolution Optical [Oi] Survey, Andrea Banzatti, Ilaria Pascucci, Suzan Edwards, Min Fang, Uma Gorti, Mario Flock
Astronomy: Faculty Publications
We present a survey of optical [O I] emission at 6300 Å toward 65 T Tauri stars at the spectral resolution of ∼7 km s−1 . Past work identified a highly blueshifted velocity component (HVC) tracing microjets and a less blueshifted low-velocity component (LVC) attributed to winds. We focus here on the LVC kinematics to investigate links between winds, jets, accretion, and disk dispersal. We track the behavior of four types of LVC components: a broad and a narrow component (“BC” and “NC,” respectively) in LVCs that are decomposed into two Gaussians which typically have an HVC, and single-Gaussian LVC …
Modeling T Tauri Winds From He I Λ10830 Profiles, John Kwan, Suzan Edwards, William Fischer
Modeling T Tauri Winds From He I Λ10830 Profiles, John Kwan, Suzan Edwards, William Fischer
Astronomy: Faculty Publications
The high opacity of He I λ10830 makes it an exceptionally sensitive probe of the inner wind geometry of accreting T Tauri stars. In this line, blueshifted absorption below the continuum results from simple scattering of stellar photons, a situation that is readily modeled without definite knowledge of the physical conditions and recourse to multilevel radiative transfer. We present theoretical line profiles for scattering in two possible wind geometries, a disk wind and a wind emerging radially from the star, and compare them to observed He I λ10830 profiles from a survey of classical T Tauri stars. The comparison indicates …
He I Λ10830 As A Probe Of Winds In Accreting Young Stars, Suzan Edwards, William Fischer, John Kwan, L. Hillenbrand, Andrea K. Dupree
He I Λ10830 As A Probe Of Winds In Accreting Young Stars, Suzan Edwards, William Fischer, John Kwan, L. Hillenbrand, Andrea K. Dupree
Astronomy: Faculty Publications
He I 10830 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 accretion-driven winds. In four of the stars, the profiles have the signature of resonance scattering, and they possess a deep and broad blueshifted absorption that penetrates more than 50% into the 1 m continuum over a continuous range of velocities from near the stellar rest velocity to the terminal velocity of the wind, unlike inner wind signatures seen in other spectral features. This deep and …
Helium Emission From Classical T Tauri Stars: Dual Origin In Magnetospheric Infall And Hot Wind, Georgina Beristain, Suzan Edwards, John Kwan
Helium Emission From Classical T Tauri Stars: Dual Origin In Magnetospheric Infall And Hot Wind, Georgina Beristain, Suzan Edwards, John Kwan
Astronomy: Faculty Publications
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. The diagnostic power of the helium lines lies in their high-excitation potentials, which restrict their formation to a region either of high temperature or close proximity to a source of ionizing radiation. The He I profiles are decomposed into kinematic components that support the paradigm of magnetically controlled accretion from the disk onto the stellar surface but also require a significant contribution from a hot wind. A …