Level diagram of the (1,1¹,0) and (0,4⁰,0) vibrational states of HCN near the Coriolis resonance involving the rotational levels from J = 8 to J = 12. The energy levels are adopted from Harris et al. (2006). The wavelength (Hocker & Javan 1967) and frequency (see Table 2 for exact numbers) of each transition are labelled. The red arrows highlight the astronomical laser transitions discovered in the course of this work, while the solid black arrows represent the previously detected laser lines of the HCN transitions towards IRC+10216. The dotted black line indicates the non-detected 894 GHz line (Schilke et al. 2000; Schilke & Menten 2003).