Collider effective mass ($m_{\mathrm{eff}}=p_T^{\mathrm{miss}}+{\sum }_j{p}_{Tj}$)

A scalar sum of missing transverse momentum magnitude and selected high-energy transverse momenta, used as a hard-event-scale diagnostic in some supersymmetry searches. Which jets and leptons enter must be defined. It is not an invariant mass or the solid-state effective mass, and no universal equality with a produced particle mass holds.