Study on broadening of Na D_1 and D_2 lines spectra in sodium-argon mixture

摘要

After the multiphoton ionization of sodium-argon mixture, time-resolved atomic emission spectrum is used toexperimentally study the unusual phenomenon of the obviously different broadening between Na D_1 and D_2 lines spectra.The primary reason for the unusual broadening of Na D_2 line is that the spectral line of Ar I 588.9 nm overlays with NaD_2 line (589.0 nm) after ionization, and the serious self-absorption on Na D_2 line is the secondary reason. Although thereis difference of population between 3~2P_(3/2) and 3~2P_(1/2) states, the experiment result demonstrates that the differencebetween Na D lines in radiation channel will not affect the broadening of spectral profile.