SCIENTIFIC ABSTRACT

THE NEW DETECTOR SATURATION LIMITS GIVEN BY THE ISOPHOT TEAM HAVE 
IT MADE NECESSARY TO REPLACE THE THREE BRIGHTEST TARGETS IN M17SW 
BY A FAINTER PROTOSTELLAR CONDENSATION. THE TWO CONDENSATIONS IN 
M17SW WILL BE OBSERVED WITH THE SAME AOT'S AS ORIGINALLY PROPOSED. 
IT WAS ONLY NECESSARY TO REPLACE SOME OF THE FILTERS AND TO MAKE 
MINOR CHANGES OF THE MAP PARAMETERS. 
The molecular cloud cores M17SW and Mon R2 play central roles in the
discussion of star-formation processes. In both cases previous high spatial 
resolution observations show the existence of gas clumps and cool 
dust condensations. Sometimes these are related to compact IR sources.
Dependent on the launch date, we propose to measure the spectral flux 
distributions of deeply embedded pre-main sequence stars and presumably 
protostellar condensations either in M17SW or in Mon R2. Because the energy
distributions of our targets peak at or beyond 100 microns ISO is 
especially suited to supplement available submm/mm fluxes and derive
broad-band flux distributions for these examples of very early stellar 
evolutionary phases.

OBSERVATION SUMMARY
M17SW: From IPAC maps and submm/mm observations by the Bonn MPIfR
Bolometer group, we selected two protostellar 
condensations. We propose to make oversampled maps of the protostellar 
condensations with PHT-C200 (filters: 135 and 200 microns, AOT P32: 
Oversampling factor = 1) as well as single-pointed raster maps with PHT-P 
at 60 microns. Furthermore, 
the condensations should be observed in the single-pointing multi-
filter mode with PHT-P and filters 3.6, 4.85, 7.7, 11.5, and 25 microns 
(AOT P03).

Mon R2: We propose make oversampled maps at the position of Mon R2-IRS1 
with PHT-C100 and filters 60 and 100 microns, and with PHT-C200 and 
filters 135 and 200 microns (AOT P32). Furthermore, we want to get 
single-pointing multi-filter observations with PHT-P at 
wavelengths 3.6, 4.85, 7.7, 11.5, 25, and 60 microns. In addition we 
will use PHT-P to observe 5 isolated dust clumps in 
single-pointing multi-filter mode (AOT P03) with the same filters as above.