Neutrino Experiments at the LHC and the HL-LHC
High energy neutrinos are copiously produced in proton-proton collisions at the Large Hadron Collider (LHC), located at CERN, near Geneva, Switzerland. In particular, a large neutrino flux is expected in the far-forward direction. This flux is concentrated near the beam axis, reaches energies up to the TeV scale, and for electron and tau neutrinos can be dominated by heavy flavour decays at the highest energies. These features open a new experimental window for studying neutrino interactions with dedicated forward detectors, in an energy range beyond the reach of traditional accelerator-based neutrino experiments. The new FASER and SND@LHC experiments reported the first direct observations of neutrino interactions at a hadron collider using the first data from Run 3, which started in 2022. Since then, the programme has advanced to the first measurements, including charged-current neutrino-nucleon cross sections and the detection of different neutrino flavours. This article describes the forward neutrino flux at the LHC, the acceptance and detector concepts of the Run 3 experiments, and summarises the current status of collider neutrino measurements. It also discusses prospects for extending this neutrino programme towards the HL-LHC era. The collected data will also provide constraints on very forward hadron production, and enable searches for feebly interacting particles.