Long-Pulse Laser-Plasma Interactions at ${10}^{12}$-${10}^{15}$ W/${\mathrm{cm}}^2$

Laser-plasma interaction physics including absorption, plasma formation, heating, plasma expansion, and energy transport, are examined for 3-nsec Nd-laser irradiances between ${10}^{12}$ and ${10}^{15}$ W/${\mathrm{cm}}^2$. Efficient energy deposition and conditions favorable to ablative acceleration are found at ${10}^{12}$-${10}^{13}$ W/${\mathrm{cm}}^2$, whereas reduced absorption, hot electrons, and fast ions are seen at 7×${10}^{14}$ W/${\mathrm{cm}}^2$. Suitability of the observed physics to pellet fusion is discussed.