The galactic 1.809 MeV map generated from the nine year spanning mission database of the imaging gamma-ray telescope COMPTEL confirms the previously reported characteristics of the interstellar 26Al distribution extracted from reduced datasets. In coarse beside an intense alongated emission feature in the inner galactic radian, intensive 1.809 MeV emission from the Cygnus region as well as low-intensity emission from the Vela-Carina region is found. Based on multi-wavelength comparisons massive stars and their subsequent core-collapse supernovae seem to dominant the release of freshlz synthesized 26Al into the ISM at large. The Cygnus region itself contains a very rich population of massive stars. In addition to a wealth of isolated massive stars (O- and WR-stars) one finds a large number of open star clusters and quite a view OB associations. In particular, the later coagulations of stars may be useful laborartories for nucleosynthesis studies and correlated investigations. Therefore, a population synthesis model predicting the time evolution of the integral output of 26Al and 60Fe as well as kinetic energy due to intense stellar winds and supernovae and the flux of ionizing photons due to hot O- and B-stars by these associations is introduced. The effects of different initial mass spectra as well as star formation histories on the outputs is studied by changing the input parameters systematically. For applying the model to real associations the number of predicted and therefore correlated observables should be as large as possible. In many cases real observables result from interaction of the primary outputs with the surrounding medium (e.g. free-free emission from electrons in the photoionized medium). For example, an 1D thin-shell model, which is discussed and studied in detail, allows a correlated analysis of the characteristics of expanding superbubbles and the expected gamma-ray line emission. The combined model is then applied to the Cygnus region, for which the properties of the massive star population have been deduced from recent literature. Population synthesis models based on star counts in the optical waveband fail to reproduce the observations in the gamma-ray line regime as well as in other cases (e.g. free-free intensity). A recently published study of the OB asssociation Cyg OB2 in the submillimeter regime has convincingly shown the dramatic impact of extinction to optical population studies of OB associations in Cygnus. This analysis results in a factor of 3 more O-stars as previously deduced by optical studies. Therefore the richnesses have been corrected for extinction by using an CO map of the region and taking Cyg OB2 for calibration. The resulting correction factors are between 1.2 and 2, only for Cyg OB9 a fairly large factor of 3.7 was found. Nevertheless, the extinction corrected population synthesis models reproduce the observations quite nicely. The predicted 1.809 MeV flux shows only a 10% deviation from the reconstructed flux value. Futhermore, the models of the Cygnus region show a clear need for combining the nucleosynthesis model with a bubble expansion model to reproduce the spatial intensity pattern. The freshly synthesized 26Al travels quite large distances before it finally decays. Due to this the 1.809 MeV intensity pattern is considerably blurred. From model fits we deduced a mean density of the ambient medium between 10 and 40 cm^-3, consistent with what was deduced by other techniques.
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The galactic 1.809 MeV map generated from the nine year spanning mission database of the imaging gamma-ray telescope COMPTEL confirms the previously reported characteristics of the interstellar 26Al distribution extracted from reduced datasets. In coarse beside an intense alongated emission feature in the inner galactic radian, intensive 1.809 MeV emission from the Cygnus region as well as low-intensity emission from the Vela-Carina region is found. Based on multi-wavelength comparisons massive...
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