L3IA - Line for Laser Light Ion Acceleration
The main goal of L3IA project is to establish an outstanding ion beam-line operation of a laser-plasma source in Italy taking advantage of the results achieved so far in this field by the wide collaboration through joint experimental campaigns and numerical modelling. According to the project timeline, the laser-plasma source is foreseen to be ready to operate with the first step at a laser-power level of 100 TW within the middle of 2017 allowing Italy to immediately keep up with the pace of the European and international groups and laboratories involved in laser-plasma driven ion acceleration and to contribute with an advanced test facility. As a final goal (end 2018) the facility will provide reliable operation of a proton beamline at 14 MeV, implementing post acceleration and manipulation of laser-plasma driven ions, using established acceleration schemes (TNSA). At the same time, advanced acceleration mechanisms will also be explored in view of a future enhancement of the beamline.
The L3IA collaboration involves researchers from the Milan, Pisa, Bologna, Napoli and LNS INFN sites. The location of the experiment has been fixed in Pisa due to the availability of a suitable laser plant (this issue in terms of costs and man power required for the assembling and the maintenance is completely incompatible with the experiment) in the frame of the CNR ILIL Lab.
The proposal received a scientific approval for 2016 and 2017 by the INFN CSN5. CNR has guaranteed the laser power upgrade, namely the pump laser upgrade, the laser compressor components and vacuum chamber, building and services, optics, mechanical devices.
The investigation of fundamental laser-plasma ion acceleration process is a key part of the research program of CNR and the study of new acceleration regimes is a key issue for INFN. We underline that this overlap of scientific interest was one of the main reasons why this collaboration between INFN and CNR was established since the beginning.
To briefly summarize, the proposal was based on two main activities developing in parallel, namely a) the development of a new high power facility and b) the progress in the research work on laser acceleration using the existing 10 TW facility.
From January to September 2016 the group involved in L3IA was able to achieve the following goals:
- Commissioning of the new lab for final laser power amplifier
- Commissioning of the new lab for main optical compressor and interaction chamber
- Installation and test of the vacuum laser transport line from compressor to target chamber
- Design of the optical laser transport line and purchase of the components including 13 mirrors and mirror mounts, mostly remotely controlled
- Design the laser diagnostic beamline switching
- Purchase and install the pump lasers to reach 100 TW final power.
The scientific program developed in parallel, also progressed significantly, with nearly 10 scientific papers published and with the study of two different configurations for laser interaction. Different target materials were investigated (aluminium, titanium, mylar, plastics, nanostructures, gold) and a record value of 2.8 MeV has been measured for protons with a very robust and reliable TOF configuration.
