Closing in on the tip of the CMSSM stau coannihilation strip

Near the tip of the (tau) over tilde coannihilation strip in the CMSSM with a neutralino lightest supersymmetric particle chi, the astrophysical cold dark matter density constraint forces the (tau) over tilde-chi mass difference to be small. If this mass difference is smaller than m(tau), the (tau) over tilde may decay either in the outer part of an LHC detector-the disappearing track signature-or be sufficiently long-lived to leave the detector before decaying-the long-lived massive charged-particle signature. We combine searches for these signatures with conventional E-T(miss) searches during LHC Run 1, identifying the small remaining parts of the CMSSM (tau) over tilde coannihilation strip region that have not yet been excluded and discussing how they may be explored during Run 2 of the LHC.