ENSURE aims at attaining ground-breaking results in the field of superintense laser-driven ion acceleration through a multidisciplinary program with the following main, connected goals.
Design and production of innovative targets for laser-driven ion acceleration
In laser-driven ion acceleration experiments, the solid target plays a crucial role. Smart design and tight control of the target system may be used to optimize the interaction, so to obtain ion beams with improved properties. This is why one of the main goals is to design, produce and characterize innovative solid targets whose properties – controlled down to the nanometric scale – are engineered to optimize the ion acceleration regime. Some of these properties are the morphology, structure, composition, density and thickness of the target material, all of which can strongly influence the physics of interaction. This experimental activity relies on advanced techniques for preparation and characterization of nanostructured systems. As a first step, an experimental investigation of the capability of designing targets with non-conventional, desired characteristics (e.g. low average density, ultralow thickness) is going to be conducted with a specific Physical Vapor Deposition technique, i.e. nanosecond Pulsed Laser Deposition. Characterization of such materials is mainly performed by electron microscopy (SEM) and Energy Dispersive X-Ray Spectroscopy (EDXS, suitable for density measurements in low density materials), along with vibrational spectroscopy techniques (Raman). The second step consists in the design, acquisition and exploitation of new laboratory equipment to eventually have a complete facility for production and characterization of different kinds of targets of interest. In particular, new Physical Vapour Deposition instruments will be considered, such as Magnetron Sputtering and femtosecond Pulsed Laser Deposition. The ultimate step is to employ and combine all the available instruments to be able to produce targets with flexible and optimal characteristics. You can find information and updates about the new laboratories here!
Theoretical investigations of novel laser-driven ion acceleration mechanisms and interaction of laser-generated ions with matter
The physics underlying laser-matter interaction for ion acceleration is extremely complex. Many simplified analytical models exists that give useful estimates for important quantities (e.g. maximum ion energy in function of laser intensity). Anyway the strongly nonlinear, multi-scale, fully kinetic, relativistic and electromagnetic nature of the dynamics makes numerical simulations an invaluable tool. Another objective of the project is to theoretically explore new regimes of laser-matter interaction both with analytical models and numerical simulations. These studies are meant to support the experimental work by helping the interpretation of the observations, suggesting new paths for the design of future campaigns and predicting the behavior of the system under circumstances beyond our means. More specifically, this activity will concern three main aspects:
- new regimes of superintense laser absorption by matter, since it is important for the development of laser-ion sources to identify an experimental configuration (laser + target) that suitably increases the laser pulse energy absorption;
- new regimes of laser-matter interaction so to obtain analytical scaling laws of interesting properties (e.g. ion maximum energy or electron temperature) as functions of the laser and target parameters (e.g. intensity, polarization, angle of incidence, thickness, density) that will allow the prediction of some features of future experiments;
- interaction between laser-generated ions and matter so to address the production of other particles via nuclear reactions and the deposition of energy in matter.
New experimental campaigns of laser-driven ion acceleration
Target design and production along with theoretical works are oriented to the proposal, realization and interpretation of new ion acceleration experiments, especially designed for the investigation of various acceleration processes and their applications. These experimental campaigns are to be performed in some advanced facilities on top-class latest generation laser systems, with unique laser parameters and supporting instrumentation. Experimental works are carried out worldwide thanks to many international collaborations.
Applications of laser-driven ions for nuclear and materials engineering
Suitable enhancement of the ion properties can open the possibility to use them for multiple technological applications. One of the goals is to investigate and promote novel, key applications of the laser-induced ion beams, so far rarely or not at all explored, in the fields of nuclear and materials engineering. Of particular interest is the generation of ion-driven exotic nuclei and secondary particle sources (for example neutrons) which can be useful for medical applications. Not only: the laser-driven particle beams can be exploited as sources for material irradiation and characterization, which is important for the development of advanced machines involving radiation like nuclear reactors, facilities for high-energy physics and medical equipment. This is why the project aims at the design of multi-purpose particle factories in a small-lab scale that can generate beams with tailored properties to be used as irradiation sources.