Long-lived charged particles (LLCPs), i.e., charged particles stable at the collider-detector scale, with a TeV-scale mass are motivated in several scenarios for dark matter. Their discovery at future hadron colliders will be extremely exciting and give significant implication for both particle physics and cosmology.

This talk, based on arXiv:1505.02996, is about collider searches for LLCPs, at a future proton-proton 100 TeV collider as well as at the 14 TeV LHC. We found that a 100 TeV collider with 3ab^-1 data has a potential to discover the charged slepton, a benchmark candidate of LLCP, with a mass of 3-4 TeV (depending on the slepton mixing angle).

Through this work, we noticed a novel features of 100 TeV hadron colliders that affects the search. In such an extreme energy, some muons will be so energetic that lose their energy also via radiative process in the detectors, which we can utilize to distinguish LLCP from muons. We found 34% of background events are rejected with this discrimination.

I would like to focus on this novel feature, because they are not specific in LLCP searches and will important for future discussion of both detector design and collider phenomenology.