ISO-LWS study of pre-main sequence sources
Proceedings article published in 1999 by
P. Saraceno,
A. M. di Giorgio,
M. Benedettini,
A. M. Giorgio,
T. Giannini,
B. Nisini,
D. Lorenzetti,
S. Molinari,
S. Pezzuto,
L. Spinoglio,
E. Tommasi,
P. E. Clegg,
J. C. Correia,
M. J. Griffin,
M. J. Kaufman 
and other authors.
and other authors.
Abstract
We present the results obtained with the ISO Long Wavelength Spectrometer on a sample of Pre-MS sources, where several molecular lines of CO, Hensuremath 2ensuremath<?subensuremath>O and OH have been detected. The analysis of the CO lines indicates that gas temperatures as low as 200 K are consistent with the data. This would be in agreement with the relatively low abundance of water in the gas phase measured in most of the objects.