On the origin of continuum and line emission in CTTSs

Abstract

We calculated profiles of CIV 1550, Si IV 1400, NV 1240 and OVI 1035 doublet lines using results of 3D MHD simulations of disc accretion onto young stars with dipole magnetic field. It appeared that our calculations can not reproduce profiles of these lines observed (HST/GHRS-STIS and FUSE) in CTTSs's spectra. We also found that the theory predicts much larger C IV 1550 line flux than observed (up to two orders of magnitude in some cases) and argue that the main portion of accretion energy in CTTSs is liberated outside accretion shock. We conclude that the reason of disagreement between the theory and observation is strongly non-dipole character of CTTS's magnetic field near its surface.