Collisional broadening of saturated absorption in neon

Saturation spectroscopy involving laser light fields of two different frequencies has been applied to the investigation of Ne*-Ne collisions in an absorptive neon discharge. The pressure broadening of the saturation signals is interpreted in terms of “weak” collisions. Half the signal width results from velocity shifts of 2p ₄ atoms rather than from oscillator dephasing. The mean velocity shift is considerably larger than in collisions with helium atoms.