Calcium II infrared triplet line models in classical T Tauri stars

We study the formation of the calcium II infrared triplet lines 8498 A, 8542 A and 8662 A, in the accreting magnetospheric flows of Classical T Tauri stars (CTTS), and present a grid of models for a large range of magnetospheric conditions. We apply our models to the interpretation of multi epoch observations of the CTTS DI Cep. We find that these lines form in the magnetospheric infall and that the variability of the Call triplet lines in DI Cep car. be explained in the context of changes in the mass accretion rate/temperature of the accretion column gas.