  The significant neutrino flux at high rapidity at the LHC motivates dedicated
forward detectors to study the properties of neutrinos at TeV energies. We
investigate magnetic dipole interactions between the active neutrinos and new
sterile states at emulsion and liquid argon experiments that could be located
in a future Forward Physics Facility (FPF) downstream of the ATLAS interaction
point. The up-scattering of neutrinos off electrons produces an electron recoil
signature that can probe new regions of parameter space at the High Luminosity
LHC (HL-LHC), particularly for liquid argon detectors due to low momentum
thresholds. We also consider the decay of the sterile neutrino through the
dipole operator, which leads to a photon that could be displaced from the
production vertex. FPF detectors can test sterile neutrino states as heavy as 1
GeV produced through the dipole portal, highlighting the use of high energy LHC
neutrinos as probes of new physics.
