On the coverage of neutralino dark matter in coannihilations at the upgraded LHC

Understand

In the supersymmetric models, the coannihilation of the neutralino DM with a lighter supersymmetric particle provides a feasible way to accommodate the observed cosmological DM relic density.

• Such a mechanism predicts a compressed spectrum of the neutralino DM and its coannihilating partner, which results in the soft final states and makes the searches for sparticles challenging at colliders.
• On the other hand, the abundance of the freeze-out neutralino DM usually increases as the DM mass becomes heavier.
• This implies an upper bound on the mass of the neutralino DM.