Top panels: observed spectra of CN 1–0 (left) and CN 2–1 (right) shown in black. We also show the best-fit LTE model (using the CASSIS software) corresponding to T_ex = 3 K, v_LSR= 69.5 km s^-1, Δv = 0.6 km s^-1, and N_CN = 5.8×10¹³ cm^-2. The data and the relevant best-fit model spectra are enlarged in the four panels below. The details of the CN(1–0) transitions are middle row left: 1, 1/2, 1/2–0, 1/2, 3/2 and right: 1, 1/2, 3/2–0, 1/2, 1/2; bottom row left: 1, 1/2, 3/2–0, 1/2, 3/2.