Isochoric heating of solid aluminum by ultrashort laser pulses focused on a tamped target

We have studied the K-shell emission of an Al plasma which was generated by focusing a high contrast 150 fs laser pulse at a wavelength of 395 nm and intensity of 5 x 10(17) W/cm(2) on a flat Al target tamped by a thin surfac e layer of MgO. The measured resonance lines (Ly(alpha), He-alpha, and He-b eta) and their Li-like and He-like satellites are extremely broadened and s how a red polarization shift. Analysis of the Ly(alpha) and He-beta satelli tes yields an electron temperature of approximate to 300 eV and an electron density of (5-10) x 10(23) cm(-3). [S0031-9007(99)09405-3].