Quasi-cw lasing due to transitions from the resonance 1P1 to the metastable 1D2 level of the calcium atom

A description is given of the method and the results are reported of an experiment in which quasi-cw lasing was obtained as a result of transitions from a resonance to a metastable level of the calcium atom without the use of any special impurities to quench the lower metastable state. Under these experimental conditions the metastable level was depopulated not as a result of collisions of the second kind or as a result of a chemical reaction, but because of the ionization, electron-impact excitation, and diffusion of metastable atoms to the discharge tube wall.