Scattering and Neutrino Detector

SND will primarily observe neutrinos in the pseudorapidity range of 7.2 to 8.6. It will detect the scattering properties of the neutrinos in this yet unexplored range and complement the observation range of FASERnu.[2][3][11] The neutrinos in this range come from the decay of heavy quarks such as charm decays (c → s + ${\textstyle \mathrm {W^{\pm }} }$ : charm quark decaying into a strange quark and a W boson), and hence SND aims to give valuable insights into the physics of heavy quark production. The charmed-hadron production studies will also provide data to constrain the gluon parton distribution function in the low Bjorken-x region.[5][6] In its first operational run, i.e. the LHC's Run-3 between 2022 and 2025, SND is expected to detect and study about 2000 high-energy neutrinos.[5][11]

The Feebly Interacting Particles (FIPs) are theorized to be produced in the proton-proton collisions. SND has the potential to detect two types of FIPs; stable FIPs by observing their scattering from the atoms (mostly protons) in the detector target section, and unstable FIPs which could decay inside the detector itself.[6] The light-dark matter particles hypothesized with scattering properties similar to the neutrinos, and which interact with the Standard Model particles through ‘portal mediators’, could also be possibly detected as FIPs,[12] although they will have to be separated from the neutrino scattering background. One basic criterion for such a separation would be to observe the number of inelastic and elastic collision events. Neutrinos usually scatter inelastically due to the high mass of their mediators (W and Z bosons). Thus more than the predicted number of elastic collisions will hint at light dark matter scattering events.[6][11]