X-ray radiation from ions with K-shell vacancies

Abstract New types of space resolved X-ray spectra produced in light matter experiments with high intensity lasers have been investigated experimentally and theoretically. This type of spectra is characterised by the disappearance of distinct resonance line emission and the appearance of very broad emission structures due to the dielectronic satellite transitions associated to the resonance lines. Atomic data calculations have shown, that rather exotic states with K-shell vacancies are involved. For quantitative spectra interpretation we developed a model for dielectronic satellite accumulation (DSA-model) in cold dense optically thick plasmas which are tested by rigorous comparison with space resolved spectra from ns-lasers. In experiments with laser intensities up to 10 19 W/cm 2 focused into nitrogen gas targets, hollow ion configurations are observed by means of soft X-ray spectroscopy. It is shown that transitions in hollow ions can be used for plasma diagnostic. The determination of the electron temperature in the long lasting recombining regime is demonstrated. In Light-matter interaction experiments with extremely high contrast (up to 10 10 ) short pulse (400 fs) lasers electron densities of n e ≈3×10 23 cm −3 at temperatures between kT e =200–300 eV have been determined by means of spectral simulations developed previously for ns-laser produced plasmas. Expansion velocities are determined analysing asymmetric optically thick line emission. Further, the results are checked by observing the spectral windows involving the region about the He α -line and the region from the He β -line to the He-like continuum. Finally, plasmas of solid density are characteristic in experiments with heavy ion beams heating massive targets. We report the first spectroscopic investigations in plasmas of this type with results on solid neon heated by Ar-ions. A spectroscopic method for the determination of the electron temperature in extreme optically thick plasmas is developed

Deliberative Mini-Publics: Core Design Features

This working paper identifies core design features of a deliberative mini-public (DMP). It aims to provide clarity on what distinguishes a DMP from other forms of citizen engagement and participation by characterising its normative foundations and setting out its key features under a series of discrete headings that can be used as a resource by anyone designing, implementing, or studying DMPs. </p

Detailed studies of the transverse beam characteristics of laser produced ion beams

We present the first systematic measurement of the transverse parameters of laser produced proton beam. We find a similarity for the shape of the accelerating sheath, which is always close to a parabola. We find also a similarity for the relation between source size and proton energy with the maximum source size and proton energy as a free parameter, which is confirming the similarity we already found for the sheath shape. This is of particular interest for the application of laser produced proton beams as it shows the scalability of the transverse beam parameter