Guido Fuchs
University of Kassel
Molecules around Late-type stars seen in the infrared at high spectral resolution using EXES on SOFIA
Our universe is full of molecules. Most molecules have been discovered with the help of radio or MM telescopes based on their rotational spectra. But molecules can also be detected unambiguously in the infrared (IR) range. Here, even those can be detected that do not have a permanent electric dipole moment. If available IR high-resolution laboratory spectra can be used to identify molecules from astrophysical observations. The molecular envelopes around aging stars provide an excellent opportunity to study molecular species and also the dynamics of their environment like the outflows, shock waves, the expansion of molecular shells or the infall of material into a star. For this purpose, observations with the SOFIA aircraft telescope using the EXES spectrpgraph were performed as well as observations using the TEXES instrument at the IRTF telescope on Mauna Kea. Hawaii on selected astronomical objects. Example IR spectra from hypergiant stars such as VY CMa and NML Cyg will be presented. With the help of the high-resolution spectra, molecular abundances, ambient temperatures, and dynamical processes can be determined. This will be demonstrated on the molecule silicon monoxide (SiO), ammonia (NH3) and others.
