4.7 Article

Global 3D simulations of disc accretion on to the classical T Tauri star BP Tauri

Journal

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
Volume 413, Issue 2, Pages 1061-1071

Publisher

OXFORD UNIV PRESS
DOI: 10.1111/j.1365-2966.2010.18193.x

Keywords

accretion, accretion discs; magnetic fields; MHD; stars: magnetic field

Funding

  1. NASA through NASA Advanced Supercomputing (NAS) Division at Ames Research Center
  2. NASA Center for Computational Sciences (NCCS) at Goddard Space Flight Center
  3. NSF [AST0709015, AST-0807129]
  4. NASA [NNX08AH25G]
  5. NASA [NNX08AH25G, 101463] Funding Source: Federal RePORTER
  6. Direct For Mathematical & Physical Scien
  7. Division Of Astronomical Sciences [1008636] Funding Source: National Science Foundation
  8. Division Of Astronomical Sciences
  9. Direct For Mathematical & Physical Scien [0807129] Funding Source: National Science Foundation

Ask authors/readers for more resources

We performed global three-dimensional magnetohydrodynamic simulations of accretion on to a star with magnetic field and other properties close to those observed in the classical T Tauri star BP Tau. We observed in the simulations that the disc is disrupted by the dipole component and matter flows towards the star in two funnel streams which form two accretion spots below the dipole magnetic poles. The octupolar component becomes dynamically important very close to the star and it redirects the matter flow to higher latitudes. The spots are meridionally elongated and are located at higher latitudes, compared with the pure dipole case. A series of simulation runs were performed at different accretion rates. We found that a 1.2 kG dipole field truncates the disc at a distance comparable to the corotation radius if the accretion rate is (1.4-2) x 10-9 M-circle dot yr-1, which is at the lower end of the observationally derived values. If the accretion rate is somewhat higher, 8.5 x 10-9 M-circle dot yr-1, then the disc is truncated at r approximate to 3.6R(star), which is a less favourable situation for the slowly rotating BP Tau. The magnetic torque acting on the star is also small; however, it is probably sufficient to support rotational equilibrium at the present state of slow rotation. Disc-magnetosphere interaction leads to inflation of the field lines and to the formation of magnetic towers above and below the disc. The magnetic field of BP Tau is close to potential inside the magnetospheric surface, where magnetic stress dominates over the matter stress. However, it strongly deviates from potential at larger distances from the star.

Authors

I am an author on this paper
Click your name to claim this paper and add it to your profile.

Reviews

Primary Rating

4.7
Not enough ratings

Secondary Ratings

Novelty
-
Significance
-
Scientific rigor
-
Rate this paper

Recommended

No Data Available
No Data Available