flavorselectrons

Flavorselectrons are the scalar supersymmetric partners of leptons that carry flavor quantum numbers in theories that extend the Standard Model with supersymmetry. In the Minimal Supersymmetric Standard Model (MSSM), sleptons come in three flavors corresponding to the electron, muon, and tau: selectrons, smuons, and staus. When flavor structure is included in the soft supersymmetry-breaking terms, the slepton mass matrices can have off-diagonal entries, causing mixing among flavors. The physical sleptons then appear as mass eigenstates that are mixtures of the original flavor states; these eigenstates are often described as flavor-selectron states.

The slepton sector typically involves left-handed and right-handed components, leading to a 6x6 mass matrix that mixes flavor and chiral states. Diagonalizing this matrix yields mass eigenstates whose flavor content determines their couplings to neutralinos, charginos, and gauge bosons. Flavor mixing in the slepton sector provides a source of lepton flavor violation (LFV) in SUSY processes, contributing to loop-induced decays such as muon to electron gamma and to other LFV observables. The strength of these effects is constrained by experimental bounds on LFV processes as well as by direct searches for sleptons.

Phenomenologically, flavor-selectrons can be produced at high-energy colliders and decay into a lepton plus missing energy, with potential flavor-violating final states if mixing is sizable. The current experimental status places stringent limits on slepton masses and on the allowed degree of flavor mixing, with no confirmed discovery of sleptons to date. Flavor-selectrons thus play a role in testing SUSY flavor models and guiding searches for new physics at colliders.