Millimetre Observations Reveal Variability in the Inner Circumstellar Envelope of the S-type AGB Star χ Cygni

The observations reveal significant variability in the emission of the H12CN(3-2) line confined to the very close neighborhood of the S-type AGB star χ Cygni, as well as evidence for a recent mass ejection event enhanced over the red-shifted north-western octant of the circumstellar envelope.