Related papers: Magnetically modulated accretion in T Tauri stars
T Tauri stars and their discs are crucial for understanding stellar evolution and the formation of planets in low-mass systems. These stars exhibit significant variability, notably emitting intense X-ray flares due to magnetic reconnection…
We consider the accretion process in a disk with magnetic fields that are dragged in from the interstellar medium by gravitational collapse. Two diffusive processes are at work in the system: (1) "viscous" torques exerted by turbulent and…
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,…
Observations of jets from young stellar objects reveal the asymmetric outflows from some sources. A large set of $2.5$D MHD simulations has been carried out for axisymmetric viscous/diffusive disc accretion to rotating magnetized stars for…
Models of magnetically driven accretion reproduce many observational properties of T Tauri stars. For the more massive Herbig Ae/Be stars, the corresponding picture has been questioned lately, in part driven by the fact that their magnetic…
Models of magnetospheric accretion on to classical T Tauri stars often assume that stellar magnetic fields are simple dipoles. Recently published surface magnetograms of BP Tau and V2129 Oph have shown, however, that their fields are more…
The accretion and ejection of mass in pre-main sequence (PMS) stars are key processes in stellar evolution as they shape the stellar angular momentum transport necessary for the stars' stability. Magnetospheric accretion onto classical T…
The variability of young stellar objects is mostly driven by star-disk interactions. In long-term photometric monitoring of the accreting T Tauri star GI Tau, we detect extinction events with typical depths of $\Delta V \sim 2.5$ mag that…
We present a three-dimensional, time-dependent, MHD simulation of the short-term interaction between a protoplanetary disk and the stellar corona in a T Tauri system. The simulation includes the stellar magnetic field, self-consistent…
Field-channelled accretion flows occur in a variety of astrophysical objects, including T Tauri stars,magnetic cataclysmic variables and X-ray pulsars. We consider a curvilinear coordinate system and derive a general hydrodynamic…
We present observations of the classical T Tauri star DO Tau collected with the near-infrared SPIRou spectropolarimeter and precision velocimeter at the Canada-France-Hawaii Telescope from early 2020 to late 2025. Circularly polarized…
The physics of the "hot spots" on stellar surfaces and the associated variability of accreting magnetized rotating stars is investigated for the first time using fully three-dimensional magnetohydrodynamic simulations. The magnetic moment…
Aims. In this paper, we aim to measure the strength of the surface magnetic fields for a sample of five intermediate mass T Tauri stars and one low mass T Tauri star from late-F to mid-K spectral types. While magnetic fields of T Tauri…
The accretion disk around a rotating magnetic star (neutron star, white dwarf or T Tauri star) is subjected to periodic vertical magnetic forces from the star, with the forcing frequency equal to the stellar spin frequency or twice the spin…
Classical T Tauri stars (CTTSs) are young low-mass stellar objects accreting mass from their circumstellar disks. They are characterized by high levels of coronal activity as revealed by X-ray observations. This activity may affect the disk…
Aims: We determine the steady-state of an axisymmetric thin accretion disc with an internal dynamo around a magnetised star. Methods: Starting from the vertically integrated equations of magnetohydrodynamics we derive a single ordinary…
EX Lupi is the prototype of EX Lup-type stars, meaning classical T Tauri stars (cTTSs) showing luminosity bursts and outbursts of 1 to 5 magnitudes lasting for a few months to a few years. These events are ascribed to an episodic accretion…
Previous analyses of magnetospheric accretion and outflow in classical T Tauri stars (CTTSs), within the context of both the X-wind model and other theoretical scenarios, have assumed a dipolar geometry for the stellar magnetic field if it…
In young circumstellar disks, accretion--the inspiral of disk material onto the central star--is important for both the buildup of stellar masses and the outcome of planet formation. Although the existence of accretion is well documented,…
Magnetorotational instability (MRI) is the most promising mechanism behind accretion in low-mass protostellar disks. Here we present the first analysis of the global structure and evolution of non-ideal MRI-driven T-Tauri disks on…