Understanding the behavior of laser-produced tin plasma by time-resolved spectroscopy and simulations of their spectra

Extreme ultraviolet (EUV) spectra from laser-produced tin plasmas have been recorded as a function of time using an ISAN grazing incidence spectrograph to study the temporal evolution of the tin unresolved transition array (UTA) responsible for the peak EUV emission. This paper reports the experimental as well as simulated results for a 10 ns gate width with 2 ns time steps which confirm that the development and collapse of the UTA follow the temporal behavior of the laser pulse. The self-absorption features at longer wavelengths are observed particularly during plasma cooling and arise from lower ion stages ranging from Sn VI to Sn XI.

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