Cobalt is essential in gas turbines due to its excellent resistance to heat, oxidation, and mechanical wear. Accurate cobalt detection using LIBS requires careful optimization of laser parameters. This study investigates the influence of laser parameters on the spectral line profiles of cobalt plasma. Cobalt plasma was generated in the atmosphere using a second harmonic laser, and it was analyzed using various laser energies (80–126) mJ and delay times (1–3) \(\upmu \) s. Spectroscopic analysis was used to estimate plasma parameters, such as electron temperature \((T_e)\) , electron density \((n_e)\) , Debye length \((\lambda _d)\) , and plasma frequency \((f_p)\) . Higher laser energies produced more energetic plasma due to high spectral line intensity, while longer delay times reduced line intensities. The Boltzmann plot method was used to calculate the plasma temperature. With an electron temperature \((T_e)\) range of (7441–10058) K or (0.64–0.86) eV and an electron number density \((n_e)\) with the range of \(0.4 \times 10^{16}\) to \(2.5 \times 10^{16}cm^{-3}\) at 1 \(\upmu \) s, these results revealed that the laser energy influences all plasma features. The temperature reached its highest value, 10058 K at 126 mJ and 1 \(\upmu \) s delay, and then declined to 9069 K at 3 \(\upmu \) s delay with the same laser energy. This shows \((T_e)\) rises and drops by increasing the laser energy and delay times, respectively. It is confirmed that optimizing laser parameters improves plasma conditions, including line profiles, signal intensity, spectrum quality, accuracy, and sensitivity. This is an effective, reliable, and efficient method for cobalt analysis in industrial applications.
