| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1239930 | Spectrochimica Acta Part B: Atomic Spectroscopy | 2013 | 6 Pages |
•Lines of Na I, K I, Ca I–II, Mg I–II, H I, N I, O I and N2 were recorded.•Recombination determines characteristic decay time of line intensity.•Three-body recombination time was used to estimate electron density.•Excitation rate constants allow to determine relation of detection limits.
The composition of the line and band spectra of the plasma induced by a femtosecond laser pulse on the surface of sea water is determined. The temporal behaviors of the intensity of the continuum and the Ca II, Mg II and Na I lines are investigated. It is shown that the time dependence of the intensity of the Na I line is described by a monoexponential function. The characteristic decay times of the line intensities of Mg II and Na I were used to estimate the three-body recombination times. Using these values, we estimate the electron number density and the feasibility of Local Thermodynamic Equilibrium (LTE) criterion. A method involving excitation rate constants is proposed for the comparison of detection limits. For a plasma generated on a liquid surface, the following relation among detection limits will be obtained: LOD(Na) < LOD(K) < LOD(Ca) < LOD(Al) < LOD(Mg) < LOD(Zn).
