Hi pullbangdead,
You are right to be doubtful. I don't think what you're referring to is really fluorescence because by definition, fluorescence requires a photon to be absorbed by the fluorescing molecule. No absorption takes place when a laser ionizes a gas. It's more like the photoelectric effect seen in solar cells etc. The plasma gives off light (if i remember correctly) because of the electron's relaxation back to ground state after recombining with positively charged gas ions.
You are right to be doubtful. I don't think what you're referring to is really fluorescence because by definition, fluorescence requires a photon to be absorbed by the fluorescing molecule. No absorption takes place when a laser ionizes a gas. It's more like the photoelectric effect seen in solar cells etc. The plasma gives off light (if i remember correctly) because of the electron's relaxation back to ground state after recombining with positively charged gas ions.