kuplimaton

Kuplimaton is a hypothetical elementary particle proposed within certain beyond-the-Standard-Model theories that extend the visible sector with a hidden or dark sector. In proposed variants, kuplimaton can act as a light boson that mediates interactions between ordinary matter and a hidden sector, or as a portal particle linking the two sectors. Depending on the model, it may be scalar, pseudoscalar, or vector, though it is often described as a weakly coupled, light vector boson. The particle is typically assumed to have a small mass, spanning sub-eV to MeV scales, and very feeble couplings to Standard Model particles, often via kinetic mixing with the hypercharge gauge field or through higher-dimensional operators.

Physically, kuplimaton is invoked to address anomalies or to realize specific phenomenological goals, such as explaining dark matter properties, modifying early-Universe cosmology, or providing a testable portal between sectors. Theoretical frameworks explore production mechanisms in particle colliders, beam-dump experiments, and various astrophysical environments. Decay channels, if any, depend on the couplings; possible decays include photons, electron-positron pairs, or invisible final states.

Status and reception: there is no experimental evidence for kuplimaton. It is one among several proposed light, weakly interacting particles and is subject to constraints from a range of experiments and observations, including stellar cooling limits, cosmic microwave background data, and laboratory searches. The idea remains speculative and is actively discussed in theoretical and experimental communities as part of broader efforts to probe dark sectors.

See also: dark photon, hidden sector, portal models, beyond Standard Model.