VLTI+ALMA imaging of potential planet-formation processes in the pre-transitional disc of V1247 Ori

In this talk we present the results from our multi-wavelength, multi-epoch high-angular resolution imaging campaign on the pre-transitional V1247 Ori. Our observations cover the wide wavelength range from the visible (SPHERE), near-IR (VLTI+NACO+Keck+Subaru), mid-IR (VLTI+Gemini), to the sub-mm (ALMA, SMA). We detect extreme asymmetries on scales from 5 to 150 au that we interpret as signposts of ongoing planet formation. VLTI interferometry reveals optically-thick dust near the dust sublimation radius as well as an extended disc gap that is filled with a population of very small dust grains. Further out in the disc, our ALMA 0.04"-resolution imaging reveals a ring-shaped inner disc component with a prominent asymmetry and a sharply confined crescent structure, resembling morphologies seen in theoretical models of vortices formation. In the near-IR we detect a strong asymmetric structure that moved in position angle (PA) from -52° to +38° within 22 months, consistent with Keplerian motion of a companion on an 5 au orbit. This companion candidate is located too close to trigger the vortex, but might be responsible for clearing the region inside the ring observed with ALMA+VLTI.