A chemical inventory of the S-type AGB star chi Cygni based on Herschel/HIFI observations of circumstellar line emission The importance of non-LTE chemical processes in a dynamical region
Schoier, F. L × Maercker, M Justtanont, K Olofsson, H Black, J. H Decin, Leen de Koter, A Waters, R #
Astronomy & Astrophysics vol:530 pages:-
Context. S-type AGB stars (C/O approximate to 1) are thought to be transition objects from M-type (O-rich) AGB stars to carbon stars and as such are interesting objects in themselves. Of particular interest is to determine accurate circumstellar properties and molecular abundances, due to their predicted sensitivity to the photospheric C/O-ratio.