Rotational analysis of the C2Σ+ — X2Σ+ system of AlO

The 2-0, 1-0, 0-0 and 0-1 bands of the C²Σ⁺-X²Σ⁺ system of AlO, lying at 2391.88 Å, 2438.35 Å, 2487.32 Å and 2548.51 Å respectively were excited in a low pressure arc and photographed on a 6.6-metre concave grating spectrograph in the third order at a dispersion of 0.37 Å/mm. From the rotational analysis of these bands, the following constants have been determined: B_e′ = 0.565₃ cm.^?1 a_e′ = 0.004₈ cm.^?1 T_e =40267.0 cm.^?1 B_e″ = 0.641₃ cm.^?1 a_{″ = 0.005 7} cm.^?1