Abstract
Long-lived particles are predicted by many extensions of the
Standard Model and have been gaining interest in recent years. The
presentation will discuss a competitive proposal that substantially
extends the sensitivity in lifetime by instrumenting the existing
service shafts above the ATLAS or CMS experiments with tracking
stations. For scenarios with electrically neutral long-lived
particles with m > 1 GeV, the lifetime reach is increased by 2-3
orders of magnitude compared to currently operating and approved
future experiments at the LHC. A detector design proposal is
outlined along with projected costs.