THE ISO-SWS SPECTRUM OF P-CYGNI

The free-free IR excess and the LR emission lines of H and He I of the Luminous Blue Variable P Cygni are observed with the ISO - SWS instru ment. The observed profiles and the free-free emission are compared wi th predictions from a non-LTE model atmosphere with a stellar wind. Th e observations agree very well with a model that has the following pro perties: T-eff=18100 K, R=76 R., He/H=0.30 by number, M=3.0 x 10(-5) M. yr(-1) and v(infinity)=185 km s(-1). We observed forbidden emission lines of [Fe II], [Fe III], [Ni II], [Ne II], [Ne III] and [Si II].; From the study of the [Ne II] and [Ne III] lines we find that the Ne a bundance is about three times higher than normal. This may be due to c lumping in the CS envelope at r similar or equal to 10(3) R.