Characteristics of energy transfer of two laser systems, fibre and disc lasers, are studied in this paper. Laser induced plasma is characterised by estimating the electron temperature and the electron density in both laser systems. Based on the electron temperature and electron density, the coefficients of inverse Bremsstrahlung absorption are estimated to investigate the energy absorption by the plasma in both systems. The electron temperature is evaluated from the observed Fe I emission lines using Boltzmann plot, whereas the electron number density is determined from the broadened line of Fe I 381·58 nm. The penetration characteristics in both systems are examined to study the role of the attenuated beam by the plasma absorption. Based on the observed features, the performance of the disc and fibre lasers, in terms of energy transfer, are comparable. However, in high power densities, the disc laser has slightly deeper penetration.
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