Bands of solid CO$_\mathsf{2}$in the 2-3μm spectrum of S 140:IRS1*

We investigate the 2-3${\rm \mu m}$ISO-SWS spectrum of the luminous protostellar object S 140:IRS1. Two narrow absorption features are detected at 2.70 and 2.77 μm, which are well fitted with laboratory spectra of the ${\rm \nu_1 + \nu_3}$and the ${\rm 2\nu_2 + \nu_3}$combination modes of solid ${\rm CO_2}$. The ice in this line of sight must have been subjected to significant heating, in agreement with previously studied CO2bands. A combined laboratory fit to all CO2bands detected toward S 140:IRS1 shows, among others, the need for particle shape calculations for the CO2stretch mode. Finally, we discuss the absence of features of isolated H2O and dangling OH groups in the spectrum of S 140:IRS1.