A young triple star system with misaligned disk/orbit planes shaped by disk tearing

We present VLTI+CHARA+VLT+GPI+ALMA observations of GW Orionis, a T Tauri-star triple system with an inner pair (242 day period) and an outer companion (11 year period). We monitored the orbital motion of the stars and derived a full RV+astrometry orbit solution, which reveals that the orbital planes are misaligned with respect to each other. We imaged the circumtriple disc at near-infrared, mid-infrared, and sub-millimetre wavelengths and discovered three rings in thermal light and an asymmetric structure with radial shadows in scattered light. The inner-most ring is eccentric and strongly misaligned both with respect to the orbital planes and with respect to the outer disc. Based on the measured triple star orbits and disc properties, we conducted smoothed particle hydrodynamic simulations which show that the system is susceptible to the disc tearing effect.