ELFIE - X-ray spectroscopy of homogeneous plasmas produced by a short pulse laser at moderate intensity on very thin targets (S. Bastiani-Ceccotti)
In this experiment it is proposed the study of the radiative properties of a homogeneous plasma, characterized by a non-spectroscopic diagnostic in order to determine its hydrodynamic parameters. The objective is to have an accurate description of the hydrodynamic conditions of the plasma simultaneously with the spectral measurements. This allows minimizing the number of free parameters in the kinetic atomic codes, improving their reliability. The sub-ps laser beam of the ELFIE facility will be used at moderate intensity (5·1015 W/cm2). In this kind of interaction, hot electron production and hydrodynamic expansion during the laser pulse duration are negligible leading to a fairly homogeneous plasma. Al and KBr dot targets will be simulttaneously irradiated with one of the two 350 fs beams of the ELFIE facility (frequency doubled). The spatially resolved plasma X-ray emission will be recorded by a PET crystal in the Von Hamos geometry. The spectral range (1650-2200 eV) will cover the Al Ly and He line emission and Ne-like 2p-3d and 2s-3p Br emissions. As hydrodynamic diagnostic, a Mach-Zehnder 3w interferometer using the probe beam will be implemented. The interferograms will be simultaneously recorded on a streak camera, to have the time evolution of the density along an axis, and on a CCD, to have the 2D mapping of the density. Finally, a double-pinhole camera will permit to monitor the absence of suprathermal electrons, thus ensuring the proper interaction we aim to obtain. The diagnostics should permit to constrain some hydrocodes (MULTi, ESTHER,…), which will be then post-processed with the atomic kinetic code SPECT3D. The measurements will also be used to compare calculations issue from other atomic physics codes (PPP, SCRAM).
ELFIE: S45-47 / 2017