Integration studies

The currently proposed location of the experiment is the experimental zone PPE138, on the H8 beam line of the CERN SPS, in the EHN1 surface area. Detailed integration studies were carried out in 2020-2021 by the CERN-EA group and are extensively reported in A. Gerbershagen et al., Nuclear Inst. and Methods in Physics Research, A 1047 (2023) 167887 (link). Two set-up of the experiment are foreseen: a “high energy” set-up, with a thicker hadron absorber and a larger distance between the target and the muon spectrometer, and a “low energy” set-up where this distance is reduced and the hadron absorber is thinner. In this way, the kinematic region around y=0 in the CMS can be covered at the various collision energies that will be studied.

The physics program of the experiment requires high heavy-ion beam intensities, of the order of 10^7 Pb ions/spill. Careful radio-protection studies are needed, to design an appropriate screening of the experimental zone. These studies, carried out by the HSE-RP group, have demonstrated that it is feasible to bring the dose, externally to the zone, to <3μSv/h.

Screening of the experimental zone (grey=concrete, brown=iron)
Expected dose for a Pb beam of 107 Pb/20 s spill