Development of foam-based layered targets for laser-driven ion beam production

We report on the development of foam-based double-layer targets (DLTs) for laser-driven ion acceleration. Foam layers with a density of a few mg cm-3 and controlled thickness in the 8-36 μm range were grown on μm-thick Al foils by pulsed laser deposition (PLD). The DLTs were experimentally investigated by varying the pulse intensity, laser polarisation and target properties. Comparing DLTs with simple Al foils, we observed a systematic enhancement of the maximum and average energies and number of accelerated ions. Maximum energies up to 30 MeV for protons and 130 MeV for C6+ ions were detected. Dedicated three-dimensional particle-in-cell (3D-PIC) simulations were performed considering both uniform and cluster-assembled foams to interpret the effect of the foam nanostructure on the acceleration process

10th International Conference on X-Ray Lasers

The search for table-top and repetitive pump schemes during the last decade has been the driving force behind the spectacular advances demonstrated during the 10th International Conference on X-Ray Lasers, organized in 2006 in Berlin. Since 1986, international experts have gathered every two years at this established conference to discuss the progress in theory, experiment and application of plasma-based soft X-ray lasers. Traditionally, the conference sessions devoted to complementary and alternative sources of short wavelength radiation, such as high harmonics, XFEL or incoherent X-rays are organized so as to emphasize the role of X-ray laser research in relation to the other short wavelength sources. Grazing incidence pumping (GRIP) and seeding with high harmonics were the dominant topics of the conference. High repetition rate and portable X-ray lasers were reported to have been applied in metrology and photochemistry for the first time. The proceedings of this series of conferences constitute a comprehensive source of reference of the acknowledged state-of the-art in this specific area of laser and plasma physics. Audience: Researchers and librarie

Hybridly pumped collisional soft X-ray laser in Ne-like sulphur

We describe an experiment demonstrating XUV amplification following collisional excitation in a discharge–created plasma waveguide irradiated by a picosecond optical laser pulse. A capillary discharge was used to generate a plasma radiation pipe with a radially concave electron density profile. Temporally resolved transmission characteristics and guiding effect have been measured. An intense short laser pulse rapidly heated the electrons, producing amplification in the [MATH] transition of Ne–like S at 60.84 nm. The integrated gain–length product obtained within a 3 cm active medium with a laser energy of 0.46 J was ~6.8. The pump energy depletion has been analysed as well. This new, hybridly pumped soft X–ray laser with the transient gain offers a new way towards efficient tabletop coherent XUV sources

Temporal resolution of a transient pumping X-ray laser

We report on a time-resolved study of a Ni-like transient collisionnal X-ray laser with a resolution as high as 1.9 ps. The FWHM duration of the Ni-like x-ray laser pulse at 13.99 nm [MATH] line is measured to be as short as [MATH] at optimum conditions of pump laser irradiation. This is about four times shorter than was estimated in previous experiments. The x-ray laser signal appears in the rising edge of the continuum emission. The x-ray laser duration rises significantly when the short (heating) pulse duration is increased and when doubling the peak-to-peak delay of the two irradiation pulses. It does not change when the short pulse energy is increased. The results presented are the first direct measurements of the temporal profile of the x-ray laser output at a high resolution