We present Keck NIRSPEC+AO high-resolution (R ∼ 25,000), mid-infrared (M-band: 4.6–5.2 μm) spectra of the protoplanetary disk CX Tau. CX Tau provides an ideal laboratory to study inner disk chemistry in a disk where the signs of radial drift of pebbles are present in the form of a compact mm dust disk and extended gas disk. Our data covers many 12CO v = 1–0 ro-vibrational transitions, in addition to 13CO and 12CO v = 2–1. We find no evidence for CO emission in the inner disk of CX Tau at the level of 8 × 1016 cm−2, but do detect narrow, blueshifted absorption at ∼−6 km s−1. A rotation diagram analysis shows that the gas temperature ranges from about 10 to 350 K, with column densities ∼9 × 1015 and 3 × 1017 cm−2, respectively. In addition to our Keck-NIRSPEC spectra, we create line maps from archival JWST-MIRI IFU data using custom JDISCS reduction techniques. These maps show spatially extended (∼500 au) H2 and [ Ne ii]. The blueshifted CO absorption and extended H2 and [Ne ii] are evidence of a photoevaporative disk wind. We estimate a wind mass-loss rate from the H2 S(1) line of ∼10−9 M ⊙ yr−1, which is approximately equal to the stellar accretion rate and suggests that CX Tau is in the early stages of disk dispersal.
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