Miao Wen-Yong

Rosseland Mean Opacity of a High-Z Mixture Plasma

An eight-beam 0.351-µm laser with pulse duration of about 1.0ns and energy of 260 J per beam was injected into a cylindrical cavity to generate intense x-ray radiation on the Shengguang II high power laser facility. A mixture foil of gold and gadolinium and a gold foil were attached on portion of a diagnostic hole in the mid-plane of the cavity and ablated by the intense x-ray radiation. The propagating time of the radiation heat wave in the mixture and the pure gold foil were measured with soft-x-ray spectrometer and by adopting space- and time-resolved measurement technology, respectively. The results show that the mixture of gold and gadolinium has higher Rosseland mean opacity than the gold sample in our experiment.

Progress and plans of X-ray temporal and spatial diagnosis technology of Shenguang facilities

In the field of indirect-drive inertial confinement fusion, temporal and spatial diagnosis of X-ray is very important to the imploded process researches and the simulate procedure verification. According to the temporal, spatial and spectral characteristics of X-ray radiation, many X-ray imaging diagnosis devices were successfully developed. Along with the development of ICF research, especially the Shenguang III facility establishment, our X-ray imaging diagnosis capability has been increasingly powerful. Some of the novel diagnosis equipment even have more excellent characteristics than that kind of diagnosis equipment abroad.

Progress of indirectly driven implosion experiments

Achieving ignition via inertial confinement approach is of strong application value and important science significance. It is also a project of large scale that depends on the national strength. Involving theory, target fabrication, diagnostics, and laser facilities, integrated implosion experiment plays an important role in the research of ICF. Since the first successful neutron production with directly driven implosion in the 80’s, the quasi one-dimensional implosion performance dominated by shock compression was demonstrated in the period of 1990–2010, and the quasi one-dimensional implosion performance dominated by inertial compression was achieved in recent years. All of these facts definitely show the progress on improving the performance of integrated implosion. With the completion of SG-III laser facility, and in the situation of facing frustration in the US ignition program, there is grand opportunity and challenge when we are exploring toward the ignition parameter space with higher convergence ratio and lower adiabat.