GIARPS/GRAVITY Survey: Broad-Band 0.44–2.4 Micron High-Resolution Spectra of T-Tauri and Herbig AeBe Stars – Combining High Spatial and High Spectral Resolution Data to Unveil the Inner Disc Physics

The GIARPS/GRAVITY survey aims to obtain a set of high spatial and spectral resolution data for a sample of T-Tauri and Herbig AeBe stars (∼100 objects) selected from the VLTI/GRAVITY GTO sample of Young Stellar Objects (YSOs). GIARPS is a broad-band spectrometer combining HARPS-N and GIANO which allows high-resolution spectra from 0.44 μm (R ∼ 115, 000) to 2.44 μm (R ∼ 50, 000) in one observation. By combining this high spectral resolution with the high spatial resolution (∼1 mas) of GRAVITY, a view of unprecedented detail can be obtained of the innermost regions of circumstellar discs in YSOs spanning a wide range of masses (0.1–5 M⊙) and ages (105–107 yr). The ultimate goal is to model the accretion and ejection mechanisms, and study how they evolve as a function of YSO mass and age, using the spatially and spectrally resolved atomic and molecular lines from the inner gaseous regions.