Abstract
High-resolution observations show that oscillations and waves in solar filament fine-structures, called threads, are common and that they are usually damped in a few periods. In addition, some observations suggest that groups of near threads oscillate coherently (in phase). Observers have also reported the presence of material flows in such filament fine-structures. Here, we investigate theoretically the non-adiabatic MHD oscillations supported by a single cylindrical thread and by groups of threads. The effect of the non-adiabatic mechanisms (radiation, thermal conduction and heating) and the mass flows on the attenuation of oscillations is assessed. We finally find that the existence of wave modes with a collective dynamics, i.e. those that produce significant perturbations in all threads, is only possible for very particular values of the plasma physical conditions and flow velocities within threads.