The Lowest Submillimeter-Wave Transitions of CH: The Laboratory Measurement of the Rest Frequencies

The lowest rotational transitions of CH in the ground electronic state (X2Pi), J=3solm0;2, N=1--J=1solm0;2, N=1, have been observed in the laboratory in the 532.8 and 536.8 GHz regions. All six possible hyperfine components are identified, and the precise transition frequencies are determined.