The Potential of EuPRAXIA@SPARC_LAB for Radiation Based Techniques

Abstract

A proposal for building a Free Electron Laser, EuPRAXIA@SPARC_LAB, at the Laboratori Nazionali di Frascati, is at present under consideration. This FEL facility will provide a unique combination of a high brightness GeV-range electron beam generated in a X-band RF linac, a 0.5 PW-class laser system and the first FEL source driven by a plasma accelerator. The FEL will produce ultra-bright pulses, with up to 10 12 photons/pulse, femtosecond timescale and wavelength down to 3 nm, which lies in the so called “water window”. The experimental activity will be focused on the realization of a plasma driven short wavelength FEL able to provide high-quality photons for a user beamline. In this paper, we describe the main classes of experiments that will be performed at the facility, including coherent diffraction imaging, soft X-ray absorption spectroscopy, Raman spectroscopy, Resonant Inelastic X-ray Scattering and photofragmentation measurements. These techniques will allow studying a variety of samples, both biological and inorganic, providing information about their structure and dynamical behavior. In this context, the possibility of inducing changes in samples via pump pulses leading to the stimulation of chemical reactions or the generation of coherent excitations would tremendously benefit from pulses in the soft X-ray region. High power synchronized optical lasers and a TeraHertz radiation source will indeed be made available for THz and pump–probe experiments and a split-and-delay station will allow performing XUV-XUV pump–probe experiments.

Progress and Perspectives of Spectroscopic Studies at Carbon K-edge Using Novel Soft X-ray Pulsed Sources

“…Their construction will expand FEL research and technology to new concepts and opportunities, also relying on the plasma-based acceleration. The AQUA beamline spectral domain matches the core absorption edge of carbon, and it will be ideal to perform experiments similar to those reviewed in this paper [63].…”

The INFN-LNF present and future accelerator-based light facilities

“…The energy range of this FEL beam will allow performing spectroscopic experiments looking at the K-edges of “light” atoms, such as carbon and nitrogen, and at the L-edges of “heavy” atoms, including some 3d transition metals. The applications are manyfold and include the study of superconductors, magnetic systems, warm-dense matter, bio-metallic complexes, and metalloproteins, just to provide some examples [ 20 ].…”

ARIA—A VUV Beamline for EuPRAXIA@SPARC_LAB

“…The first designed FEL beamline, called AQUA [20][21][22], will operate in the water window at 3-4 nm, as required by the EuPRAXIA design study, according to the beam parameters reported in Table 1. This beamline will use the full undulator length available to the project and very high quality electron beams.…”