Bands of solid CO2 in the 2-3 mu m spectrum of S 140 : IRS1

We investigate the 2-3 mum ISO-SWS spectrum of the luminous protostellar ob ject S 140:IRS1. Two narrow absorption features are detected at 2.70 and 2. 77 mum, which are well fitted with laboratory spectra of the nu (1) + nu (3 ) and the 2 nu (2) + nu (3) combination modes of solid CO2. The ice in this line of sight must have been subjected to significant heating, in agreemen t with previously studied CO2 bands. A combined laboratory fit to all CO2 b ands detected toward S 140:IRS1 shows, among others, the need for particle shape calculations for the CO2 stretch mode. Finally, we discuss the absenc e of features of isolated H2O and dangling OH groups in the spectrum of S 1 40:IRS1.