The wind and the magnetospheric accretion onto the T Tauri star S Coronae Australis at sub-au resolution

Aims. To investigate the inner regions of protoplanetary discs, we performed near-infrared interferometric observations of the classical T Tauri binary system S？CrA.Methods. We present the first VLTI-GRAVITY high spectral resolution (R ~ 4000) observations of a classical T Tauri binary, S？CrA (composed of S？CrA？N and S？CrA？S and separated by ~1.？4), combining the four 8m telescopes in dual-field mode. Results. Our observations in the near-infrared K-band continuum reveal a disc around each binary component, with similar half-flux radii of about 0.1 au at d ~ 130？pc, inclinations (i = 28 ± 3° and i = 22 ± 6°), and position angles (PA = 0°± 6° and PA = –2°± 12°), suggesting that they formed from the fragmentation of a common disc. The S？CrA？N spectrum shows bright He？i and Brγ line emission exhibiting inverse P？Cygni profiles, typically associated with infalling gas. The continuum-compensated Brγ line visibilities of S？CrA？N show the presence of a compact Brγ emitting region whose radius is about ~0.06？au, which is twice as big as the truncation radius. This component is mostly tracing a wind. Moreover, a slight radius change between the blue- and red-shifted Brγ line components is marginally detected.Conclusions. The presence of an inverse P？Cygni profile in the He？i and Brγ lines, along with the tentative detection of a slightly larger size of the blue-shifted Brγ line component, hint at the simultaneous presence of a wind and magnetospheric accretion in S？CrA？N