We present UKIRT UIST spectra of Sakurai ’ s Object ( =V4334 Sgr ) showing CO fundamental band absorption features around 4.7 \mu m. The line-centres are at heliocentric radial velocity of - 170 \pm 30 km s ^ { -1 } .
The number and relative strengths of the lines indicate a CO gas temperature of 400 \pm 100 K and CO column density of 7 ^ { +3 } _ { -2 } \times 10 ^ { 17 } cm ^ { -2 } .
The gas was moving away from the central star at an average speed of \sim 290 \pm 30 km s ^ { -1 } in 2003 September .
The lines appeared sometime between mid 1999 ( well after the opaque dust shell formed ) and mid 2000 and may have been somewhat more blue–shifted initially than they are now .
The observed CO velocity and temperature indicate the continued presence of a fast wind in the object , previously seen in the He i 1.083 \mu m line beginning just prior to massive dust formation , and more recently in atomic and ionized lines .
The dust continuum is consistent with a temperature of 350 \pm 30 K , indicating continued cooling of the shell .
The similar CO temperature suggests that the bulk of the CO absorption occurs just outside of the dust continuum surface .