Physical parameter dependence of the x-ray generation in intense laser cluster interaction
Résumé
The availability of high-performance ion storage rings, of swift ion and cluster accelerators producing intense beams with excellent optical quality and of ion sources providing highly charged slow ions, have enabled a series of benchmark experiments on particle – matter collisions. In addition, developments in target preparation techniques along with significant advances in large area many-particle detection devices of extreme spatial and time resolution have allowed to study in detail the dynamics of collision products. The whole research activity in this field covers a wide range of scientific topics: New generation of prominent experiments concerns the interaction of atomic, molecular or cluster ions, over a large range of energy (from eV to GeV), with matter – matter including namely electrons, plasmas, atoms, molecules, clusters and solids. Nowadays, in many cases, both the states of these incoming ions and the response of the target are characterised during the collision. The fundamental goal is to probe the response of matter under the influence of strong and short pulses of electromagnetic radiation. For collisions with dilute media, high precision measurements of multiple processes cross sections are at hand and reveal shortcomings of the most sophisticated theories. The knowledge acquired on elementary process has opened the way to the investigation of the dynamics of more complex systems, like induced fragmentation of molecules or clusters. Ions interaction with electrons shows up new states of atoms, molecules and clusters. Beside the prime importance of electron-ion collisions in plasmas directly related to heavy ion inertial fusion purposes, resonances in collision cross sections provide today an alternative access to highly accurate information on atomic energy levels, and therefore a sensitive test of QED calculations (link with section 2). Finally, mechanisms responsible for strong energy deposition during ion interaction with condensed matter (bulk and surface) are determined within deep insight. These studies clearly provide crucial information for the understanding of the first stages of material modifications discussed in section 4. Beyond its own fundamental interest, the field of ion-matter interaction has also a strong impact on many other scientific domains like astrophysics and astrochemistry, atmospheric physics, radiobiology and radiation chemistry.