After three years of interruption during LS2 (Long Shutdown 2), ALICE was on time for the first collisions after a very important rejuvenation started in 2012 of its electronics, readout and acquisition systems as well as the addition of new detectors. IRFU has long been heavily involved in the ALICE muon forward spectrometer, in particular the MCH (Muon Chambers) tracking chambers, and now also in the new MFT (Muon Forward Tracker) silicon pixel tracker. The MFT will allow to extend the physics domain to additional channels by bringing a better resolution on the tracks and thus on the mass of the detected particles as well as on the extrapolation of the muon tracks to the interaction point.
IRFU has designed the SOLAR cards for the MCH (Muon CHambers) and supervised the production of the 700 cards and the 112 chassis that house them. A software embedded in each detector has also been developed by IRFU.
The MFT (Muon Forward Tracker) is a brand new detector for which IRFU, in collaboration with IN2P3, has been responsible for the coordination and a large part of the production. The installation of the MFT in the ALICE cavern took place in December 2020, in the middle of a pandemic, thanks in particular to the work of IRFU scientists stationed at CERN and to the members of the DEDIP Antenna. From the end of 2021, the MFT was able to see its first traces reconstructed. This was a very satisfying moment for the whole project team, which demonstrated the capacity of the MFT to detect with precision and efficiency the very many particles emitted during high energy collisions.
ALICE and in particular the muon spectrometer with the MFT has also successfully started its operation. Of course, many adjustments and improvements are being made to be fully ready for the lead-lead collisions at the end of the year, which are the primary goal of the ALICE experiment in 2022.
|Photo taken during the installation of the MFT detector in the ALICE experiment.||SOLAR map developed by IRFU.|