Related papers: Star-disk interaction in the T Tauri star V2129 Op…
Observations of T Tauri stars and young brown dwarfs suggest that the accretion rates of their disks scale strongly with the central stellar mass, approximately $\mdot \propto M_*^2$. No dependence of accretion rate on stellar mass is…
Aims : We aimed at constraining the accretion-ejection phenomena around the strongly-accreting Northern component of the S CrA young binary system (S CrA N) by deriving its magnetic field topology and its magnetospheric properties, and by…
We have studied numerically the evolution of protostellar disks around intermediate and upper mass T Tauri stars (0.25 M_sun < M_st < 3.0 M_sun) that have formed self-consistently from the collapse of molecular cloud cores. In the T Tauri…
The disk-outflow connection is thought to play a key role in extracting excess angular momentum from a forming proto-star. Though jet rotation has been observed in a few objects, no rotation of molecular outflows has been unambiguously…
For the first time in a classical T Tauri star, we are able to trace an accretion event signaled by an hour-long enhancement of X-rays from the accretion shock and revealed through substantial sequential changes in optical emission line…
Planets are thought to form at the early stage of stellar evolution when the mass accretion is still ongoing. RY Tau is a T Tauri type star at the age of a few Myr, with accretion disc seen at high inclination, so that line of sight crosses…
We analyze the variability in accretion-related emission lines for 40 Classical T Tauri stars to probe the extent of accretion variations in young stellar objects. Our analysis is based on multi-epoch high-resolution spectra for young stars…
The accretion of material from protoplanetary disks onto their central stars is a fundamental process in the evolution of these systems and a key diagnostic in constraining the disk lifetime. We analyze the relationship between the stellar…
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…
(Abridged) We contribute to our understanding of the evolution of young intermediate-mass stars by providing a comprehensive analysis of their lithium (Li) content. A sample of 71 intermediate-mass T Tauri (IMTT) and Herbig stars within the…
Classical T Tauri stars (CTTSs) are variable in different time-scales. One type of variability is possibly connected with the accretion of matter through the Rayleigh-Taylor instability that occurs at the interface between an accretion disc…
Measurements of masses and ages of young stars from their location in the HR diagram are limited by not only the typical observational uncertainties that apply to field stars, but also by large systematic uncertainties related to…
Protoplanetary disks around young Sun-like stars are the cradles of the vast majority of detected exoplanets. Probing these disks at multiple spatial scales is key to uncovering how planets form. We aim to spatially and spectrally resolve…
Investigating the evolution of protoplanetary disks is crucial for our understanding of star and planet formation. Several theoretical and observational studies have been performed in the last decades to advance this knowledge. FT Tauri is…
Magnetospheric accretion is a key process that shapes the inner disks of T Tauri stars, controlling mass and angular momentum evolution. It produces strong ultraviolet and optical emission that irradiates the planet-forming environment. In…
We present results of axisymmetic magnetohydrodynamic simulations of the interaction of a rapidly-rotating, magnetized star with an accretion disk. The disk is considered to have a finite viscosity and magnetic diffusivity. The main…
We present a Spitzer IRS study of variability in 14 T Tauri stars in the Taurus and Chamaeleon star-forming regions. The sample is composed of transitional and pre-transitional objects which contain holes and gaps in their disks. We detect…
The rotational evolution of accreting pre-main-sequence stars is influenced by its magnetic interaction with its surrounding circumstellar disk. Using the PLUTO code, we perform 2.5D magnetohydrodynamic, axisymmetric, time-dependent…
We construct detailed vertical structure models of irradiated accretion disks around T Tauri stars with interstellar medium dust uniformly mixed with gas. The dependence of the structure and emission properties on mass accretion rate,…
We present optical spectrophotometric monitoring of four active T Tauri stars (DG Tau, RY Tau, XZ Tau, RW Aur A) at high spectral resolution ($R \ga 1 \times 10^4$), to investigate the correlation between time variable mass ejection seen in…