Scanning Disk Rings and Winds in CO at 0.01–10 au: A High-resolution M-band Spectroscopy Survey with IRTF-iSHELL

We present an overview and first results from a $M$-band spectroscopic survey of planet-forming disks performed with iSHELL on IRTF, using two slits that provide resolving power R $\approx$ 60,000-92,000 (5-3.3 km/s). provides nearly complete coverage at 4.52-5.24 $\mu$m in one shot, covering $>50$ lines the P branches $^{12}$CO $^{13}$CO for each multiple vibrational levels, providing unprecedented information excitation emission absorption components. Some most notable new findings this are: 1) detection CO Keplerian rings $<2$ au (in HD 259431), 2) H${_2}$O ro-vibrational 5 AS 205 N), 3) common kinematic variability over timescales 1-14 years. By homogeneously analyzing together previous VLT-CRIRES cooler stars, we discuss unified view spectra where components scan disk surface across radii dust-free region within dust sublimation out to $\approx10$ au. classify fundamental types line shapes interpreted as (double-peak lines) plus low-velocity part wind (triangular lines), reflects different emitting regions (and their gas-to-dust ratio) rather than just irradiation spectrum. A disk+wind interpretation triangular naturally explains several properties observed spectra, including blue-shifts, turn into narrow high inclinations, frequency winds function stellar type.