Detector studies

Vertex spectrometer

The vertex spectrometer will be based on MAPS sensors presently under development for the ALICE ITS3 and NA60+ projects. Large area sensors will be built, thanks to the stitching technique. The present NA60+ set-up foresees from 5 up to 10 planes of MAPS, each built with 2×2 sensors (30×30 cm2)

Dipole magnet

The vertex spectrometer is immersed in the magnetic field generated by a dipole magnet. A viable candidate is the MEP48 magnet, presently stored at CERN. It has a 40 cm wide gap and can deliver up to 1.47 T

Muon spectrometer

The muon spectrometer is placed downstream of the vertex spectrometer, after a thick absorber that efficiently filters out the hadrons produced in the primary interaction. It includes six tracking stations, based on GEM detectors. Groups of two stations are positioned upstream and downstream of the toroidal magnet, while the last two stations are placed downstream of a further hadron absorber, that further helps in rejecting the hadronic background. The use of 50×100 cm2 3-GEM modules with 2D strip readout is currently foreseen. The spatial resolution will be 200 μm for stations 1-4 and 1 mm for stations 5-6.

Toroidal magnet

A working prototype of the toroidal magnet for the muon spectrometer was built at CERN in the frame of a collaboration between the CERN-DT, INFN Torino and INFN Cagliari groups, and was tested in 2021

Results of first preliminary tests can be found here

Hereafter some estimates of the properties of the full-scale magnet