End of the CMSSM coannihilation strip is nigh

A recent global fit to the constrained minimal supersymmetric extension of the Standard Model incorporating current constraints on supersymmetry, including missing transverse energy searches at the LHC, BR(B_s→μ ⁺μ^-) and the direct XENON100 search for dark matter, favors points towards the end of the stau-neutralino (τ _Ëœ1-χ) coannihilation strip with relatively large m_1/2 and 10â‰tanâ¡βâ‰40 and points in the H/A rapid-annihilation funnel with tanâ¡β ∼50. The coannihilation points typically have m_τËœ 1-m_χâ‰5 GeV, and a significant fraction, including the most-favored point, has m_τËœ1-m _χ<m_τ. In such a case, the τ _Ëœ1 lifetime would be so long that the τ_Ëœ1 would be detectable as a long-lived massive charged particle that may decay inside or outside the apparatus. We show that CMSSM scenarios close to the tip of the coannihilation strip for tanâ ¡βâ‰40 are already excluded by LHC searches for massive charged particles and discuss the prospects for their detection in the CMS and ATLAS detectors via time-of-flight measurements, anomalous heavy ionization or decays into one or more soft charged particles.