Plasma line emission from short pulse laser interactions with dense plasmas

Plasma line emission is observed in simulations of dense plasma irradiated by moderately intense light pulses of duration some tens of femtoseconds, and its scaling with density and with laser intensity is studied. Plasma emission is recorded both during the pulse where it is observed against the background spectrum of harmonics of the laser frequency as well as postpulse. Harmonics of the plasma line up to the fifth have been observed. An unexpected feature present in most of the reflected light spectra appears on the blue side of the plasma line with a central frequency omega approximately 1.5omega(p).