A possible detection of infrared emission from carbon monoxide in Comet Austin (1989c 1)

A cryogenic IR echelle grating spectrometer has been used to probe the nu = 1-0 rovibrational band of the CO molecule in Comet Austin. Line emission has been detected at the Doppler-shifted frequency expected for the cometary P(3) line, in scans which are noted to cover only the first 3000 sec of May 16, 1990 observations; this is suggested to be due to an outburst of comparable duration. No detections were made of the P(2) line, which was predicted by models to occur at the 3.5 sigma level even for relatively high coma temperatures. If the outburst was accompanied by enhanced dust production, an increase by a factor of 2.5 is consistent with the present observational data and CO/dust may have been enriched in the outbursting volume relative to the remainder of the nucleus.