Suitable instrumentation for laser-accelerated proton (ion) beams is critical for development of integrated, laser-driven ion accelerator systems. Instrumentation aimed at beam diagnostics and control must be applied to the driving laser pulse, the laser-plasma that forms at the target and the emergent proton (ion) bunch in a correlated way to develop these novel accelerators. This report is a brief overview of established diagnostic techniques and new developments based on material presented at the first workshop on 'Instrumentation for Diagnostics and Control of Laser-accelerated Proton (Ion) Beams' in Abingdon, UK. It includes radiochromic film (RCF), image plates (IP), micro-channel plates (MCP), Thomson spectrometers, prompt inline scintillators, time and space-resolved interferometry (TASRI) and nuclear activation schemes. Repetition-rated instrumentation requirements for target metrology are also addressed.

An experiment was done at the Rutherford Appleton Laboratory ͑Vulcan laser petawatt laser͒ to study fast electron propagation in cylindrically compressed targets, a subject of interest for fast ignition. This was performed in the framework of the experimental road map of HiPER ͑the European high power laser energy research facility project͒. In the experiment, protons accelerated by a picosecond-laser pulse were used to radiograph a 220 m diameter cylinder ͑20 m wall, filled with low density foam͒, imploded with ϳ200 J of green laser light in four symmetrically incident beams of pulse length 1 ns. Point projection proton backlighting was used to get the compression history and the stagnation time. Results are also compared to those from hard x-ray radiography. Detailed comparison with two-dimensional numerical hydrosimulations has been done using a Monte Carlo code adapted to describe multiple scattering and plasma effects. Finally we develop a simple analytical model to estimate the performance of proton radiography for given implosion conditions.

The scaling of the flux and maximum energy of laser-driven sheath-accelerated protons has been investigated as a function of laser pulse energy in the range of 15-380 mJ at intensities of 10(16)-10(18) W/cm(2). The pulse duration and target thickness were fixed at 40 fs and 25 nm, respectively, while the laser focal spot size and drive energy were varied. Our results indicate that while the maximum proton energy is dependent on the laser energy and laser spot diameter, the proton flux is primarily related to the laser pulse energy under the conditions studied here. Our measurements show that increasing the laser energy by an order of magnitude results in a more than 500-fold increase in the observed proton flux. Whereas, an order of magnitude increase in the laser intensity generated by decreasing the laser focal spot size, at constant laser energy, gives rise to less than a tenfold increase in observed proton flux

Abstract. The target supply system is a necessary requirement for fueling a future energy source (reactor) with a high rep-rate: 0.1-10 Hz. At the Lebedev Physical Institute (LPI), significant progress has been made in the technology based on rapid fuel layering inside moving free-standing targets that is referred to as FST (Free-Standing Targets) layering method. This allows creating a continuously or repeatable operating FST supply system, the development of which at LPI dates back to 1980s. Therefore, the LPI is in the position to propose the use of FST technologies for HiPER facility operation (conceptual design and prototype realization). Here we report on our most significant results on the development of a specialized layering module prototype for repeatable formation of HiPER free-standing cryogenic targets.