Supersymmetry breaking occurs when the action or vacuum is not invariant under the supercharges. Explicit breaking destroys the exact superalgebra, while spontaneous breaking preserves the action but gives a vacuum not annihilated by every supercharge and produces a Goldstino.
Soft supersymmetry breaking adds operators of positive mass dimension that break supersymmetry without reintroducing new ultraviolet quadratic divergences.
A sparticle is the supersymmetric partner of a Standard Model particle. It differs in spin by one half and has the opposite R-parity.
A gaugino is the spin-one-half superpartner of a gauge boson and transforms in the adjoint representation of its gauge group. Gaugino loops modify gauge-coupling beta functions above the supersymmetry-breaking threshold.
A squark is the spin-zero supersymmetric partner of a quark. It carries the same colour, weak-isospin and hypercharge quantum numbers as the corresponding quark chirality.
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Supersymmetry (SUSY) is a theoretical framework in particle physics that proposes a symmetry between two basic classes of particles: fermions (which make up matter, like electrons and quarks) and bosons (which mediate forces, like photons and gluons). In a fully realized supersymmetric model, each particle in the Standard Model of particle physics would have a superpartner with differing spin.