Submillimetre HCN Masers in Carbon-Rich AGB Stars

Learn about groundbreaking astronomical observations of hydrogen cyanide (HCN) masers in carbon-rich AGB stars through this research presentation. Explore recent findings from single-dish observations that reveal widespread emission lines in vibrationally excited states, with particular focus on two highly excited masers at 805 and 891 GHz observable through ALMA's highest frequency band. Examine ALMA observations showing intense maser emission in inner envelope regions, along with thermal emission from ground-state and vibrationally excited lines that help trace inner wind kinematics. Discover how these targets are ideal candidates for long-baseline observations achieving angular resolutions below 10 mas, as demonstrated in recent ALMA commissioning tests.