Direct Measurement of Compression of Laser-Imploded Targets Using X-Ray Spectroscopy

Compression of neon-filled glass microballoons irradiated by a four-beam laser system has been measured directly by Stark broadening, opacity broadening, and spatial profiles of ${\mathrm{Ne}}^{+9\mathrm{}}$ x-ray lines. For an 8.6-atm fill pressure and a 0.2-TW, 40-psec laser pulse, the measured compressed neon density was 0.26 g/${\mathrm{cm}}^3$ and the product $\rho R$ was 2.5 × ${10}^{-4\mathrm{}}$ ${\mathrm{g}/\mathrm{c}\mathrm{m}}^2$.