The SPARC LAB THz source driven by high-brightness electron beams

The THz source produced at the SPARC LAB test facility is able to deliver radiation pulses with time duration of few hundreds of femtoseconds and energy per pulse larger than 10 micro-Joule, corresponding to electric and magnetic fields of the order of 1MV/cm and 0.5T, respectively. The linac-driven THz radiation is produced as coherent radiation emitted by ultra-short high-brightness electron bunches. Depending on the electron bunch shaping, the THz radiation is characterized by a tunable spectral bandwidth suitable for electron beam longitudinal diagnostics, characterization of novel materials, pump-probe experiments

Study of plasma wakefield acceleration mechanism for emittance dominated regimes via hybrid and pic simulations

Electron plasma wakefield acceleration (PWFA) mechanism is a promising non conventional acceleration scheme. Nonetheless further investigation is still needed to fully uncover the instability mechanisms so to mitigate them and make PWFA an effective tool. This work focuses in this direction, we discuss the necessity to use well matched driver bunches to further mitigate witness instabilities. Specifically we propose to inject driver bunches with larger emittance than the matched one (overcompressed bunch) so to let the system reach the matching condition by itself. This preliminary results lead us to the following consideration: while a limited number of cases can be studied with a particle-in-cell code, we understand the necessity for fast systematic analysis: we briefly introduce the hybrid code Architect

Plasma boosted electron beams for driving Free Electron Lasers

In this paper, we report results of simulations, in the framework of both EuPRAXIA \cite{Walk2017} and EuPRAXIA@SPARC\_LAB \cite{Ferr2017} projects, aimed at delivering a high brightness electron bunch for driving a Free Electron Laser (FEL) by employing a plasma post acceleration scheme. The boosting plasma wave is driven by a tens of \SI{}{\tera\watt} class laser and doubles the energy of an externally injected beam up to \GeV{1}. The injected bunch is simulated starting from a photoinjector, matched to plasma, boosted and finally matched to an undulator, where its ability to produce FEL radiation is verified to yield O(\num{e11}) photons per shot at \nm{2.7}.Comment: 5 pages, 2 figure

Optical issues for the diagnostic stations for the ELI-NP compton gamma source

A high brightness electron Linac is being built in the Compton Gamma Source at the ELI Nuclear Physics facility in Romania. To achieve the design luminosity, a train of 32 bunches, 16 ns spaced, with a nominal charge of 250 pC will collide with the laser beam in the interaction point. Electron beam spot size is measured with optical transition radiation (OTR) profile monitors. In order to measure the beam properties, the optical radiation detecting system must have the necessary accuracy and resolution. This paper deals with the studies of different optic configurations to achieve the magnification, resolution and accuracy in order to measure very small beam (below 30 μm) or to study the angular distribution of the OTR and therefore the energy of the beam. Several configurations of the optical detection line will be studied both with simulation tools (e.g. Zemax) and experimentally. The paper will deal also with the sensibility of optic system (in terms of depth of field, magnification and resolution) to systematic error