the Electron Ion Collider EIC (red), the LHeC (ERL against the HL-LHC beams, dark blue) and two FCC-he versions (with Pb beams corresponding to proton energies of 20 TeV -green and 50 TeV -light blue). The areas delimitated by thick brown and black lines show the regions accessible in 𝑝Pb collisions at the LHC and the FCC-hh (50 TeV) respectively, while the thin lines represent constant rapidities from 0 (right) to 6.6 (left) for each case. Acceptance is taken to be 1 • < 𝜃 < 179 • , and 0.01(0.001) < 𝑦 < 1 for the EIC (all other colliders). The saturation scale 𝑄 𝑠𝑎𝑡 shown here for indicative purposes only. Taken from [2,3].