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arXiv · astro-ph/9502061

Magnetically modulated accretion in T Tauri stars

C. J. Clarke·P. J. Armitage·K. W. Smith·J. E. Pringle
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Abstract

We examine how accretion on to T Tauri stars may be modulated by a time-dependent `magnetic gate' where the inner edge of the accretion disc is disrupted by a varying stellar field. We show that magnetic field variations on time-scales shorter than 10^5 yr can modulate the accretion flow, thus providing a possible mechanism both for the marked photometric variability of T Tauri stars and for the possible conversion of T Tauri stars between classical and weak line status. We thus suggest that archival data relating to the spectrophotometric variability of T Tauri stars may provide an indirect record of magnetic activity cycles in low-mass pre-main-sequence stars.

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C. J. Clarke, P. J. Armitage, K. W. Smith, J. E. Pringle. 1995-02-11. Magnetically modulated accretion in T Tauri stars. https://doi.org/10.1093/mnras%2F273.3.639

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