Real-time monitoring via second-harmonic interferometry of a flow gas cell for laser-plasma acceleration.

Brandi F., Giammanco F., Conti F., Sylla F., Lambert G., Gizzi. L.A.
  Venerdì 30/09   15:00 - 18:00   Edificio Psicologia 2 - Aula 2B   II - Fisica della materia
The use of gas cell for laser walafield acceleration (LWFA) offers the possibility to obtain a stable and manageable laser-plasma process, a mandatory condition for practical applications especially in multi-stage accelerators. To obtain full control of the gas particle number density $N$ real-time monitoring is necessary. Here, second-harmonic interferometry is applied to measure $N$ inside a flow gas cell designed for LWFA. Real-time monitoring is achieved, and using low-backing-pressure gas ($< 1$ bar) and different cell orifice diameters ($< 2$ mm) it is possible to finely tune $N$ up to few $10^{19}$ cm${}^{-3}$ well suited for LWFA.