Vol. 529In section 1. Letters

Probing the dust formation region in IRC +10216 with the high vibrational states of hydrogen cyanide

Dust forms in large part in the vicinity of the photosphere of AGB stars, and it is fundamental to understand the physical parameters of the gas and dust close to the stellar surface. An important step towards such an understanding is the Letter by Cernicharo et al. highlighted in this issue. The authors observed 63 transitions of HCN in 28 different vibrational states towards the C-rich AGB star IRC+10216, throwing light on the physical conditions between 1.5 and 28 stellar radii.