Related papers: The close classical T Tauri binary V4046 Sgr: Comp…

We explore the possibility that GSC 07396-00759 (spectral type M1e) is a widely separated (~2.82', or projected separation ~12,350 AU) companion to the "old" (age ~12 Myr) classical T Tauri binary system V4046 Sgr AB, as suggested by the…

Studies of magnetospheric accretion and magnetic field topology in T Tauri stars have advanced over the years, but their applications to fully convective, very-low-mass T Tauri stars remain relatively unexplored. We aim to analyze the…

The inner 0.1 AU around accreting T Tauri stars hold clues to many physical processes that characterize the early evolution of solar-type stars. The accretion-ejection connection takes place at least in part in this compact magnetized…

We have produced brightness and magnetic field maps of the surfaces of CV Cha and CR Cha: two actively accreting G and K-type T Tauri stars in the Chamaeleon I star-forming cloud with ages of 3-5 Myr. Our magnetic field maps show evidence…

We examine 3 analytic theories of magnetospheric accretion onto classical T Tauri stars under the assumption that the magnetic field strength does not vary appreciably from star to star. From these investigations we derive predicted…

The dust- and gas-rich protoplanetary disks around young stellar systems play a key role in star and planet formation. While considerable progress has recently been made in probing these disks on large scales of a few tens of astronomical…

The nature of the magnetic coupling between T Tauri stars and their disks determines not only the mass accretion process but possibly the spin evolution of the central star. We have taken a recently-published surface magnetogram of one…

Although the magnetospheric accretion model has been extensively applied to T Tauri Stars with typical mass accretion rates, the very low accretion regime is still not fully explored. Here we report multi-epoch observations and modeling of…

Magnetic fields in accretion disks play a dominant role during the star formation process but have hitherto been observationally poorly constrained. Field strengths have been inferred on T Tauri stars themselves and possibly in the…

This paper presents near-infrared spectropolarimetric and velocimetric observations of the young planet-hosting T Tauri star PDS 70, collected with SPIRou at the 3.6m Canada-France-Hawaii Telescope from 2020 to 2024. Clear Zeeman signatures…

Using the largest high-resolution spectroscopic sample to date of young, very low mass stars (VLMS) and brown dwarfs (BDs), we investigate disk accretion in objects ranging from just above the hydrogen-burning limit all the way to nearly…

Classical T Tauri stars are low-mass pre-main sequence stars with an active circumstellar environment. In this work we present the identification and study of 260 Classical T Tauri stars using LAMOST Data Release 6, among which 104 stars…

We perform three-dimensional magnetohydrodynamic simulations of magnetospheric accretion in a T Tauri star to study the accretion and wind structures in the close vicinity of the star. The gas accreting onto the star consists of the gas…

We present measurements of the longitudinal magnetic field in the circumstellar environment of seven classical T Tauri stars. The measurements are based on high-resolution circular spectropolarimetry of the He I 5876 emission line, which is…

Aims: We aim to spatially and spectrally resolve the Br-gamma hydrogen emission line with the methods of interferometry in order to examine the kinematics of the hydrogen gas emission region in the inner accretion disk of a sample of…

We analyze the highest-resolution millimeter continuum and near-infrared (NIR) scattered-light images presented to date of the circumbinary disk orbiting V4046 Sgr, a ~20 Myr old actively accreting, close binary T Tauri star system located…

We present a high spatial resolution UV to NIR survey of 44 young binary stars in Taurus with separations of 10-1000 AU. The primary results include: (1) The relative ages of binary star components are more similar than the relative ages of…

This paper exploits spectropolarimetric data of the classical T Tauri star CI Tau collected with ESPaDOnS at the Canada-France-Hawaii Telescope, with the aims of detecting and characterizing the large-scale magnetic field that the star…

We present Chandra HETGS observations of the classical T Tauri star (CTTS) V4046 Sgr. The He-like triplets of O VII, Ne IX, and Si XIII are clearly detected. Similar to the CTTS TW Hya and BP Tau, the forbidden lines of O VII and Ne IX are…

From a long time series of high resolution (R=115,000) HARPS spectra and simultaneous broad-band photometry, we report new evidence for magnetospheric accretion as well as ejection processes in the nearly edge-on classical T Tauri star AA…