We have extended our evolutionary synthesis models for Star Forming Regions
to the gamma -ray domain. Applying different yields to the resulting synth
etic populations, we obtain lightcurves of gamma -ray line emission due to
the radioactive decay of stellar nucleosynthesis products, such as Al-26 an
d Fe-60. We present here this time evolution and the application of the mod
els to regions of star. formation in our galaxy. (C) 2000 Elsevier Science
B.V. All rights reserved.