# A Trigger for Displaced Muon Pairs Following the CMS Phase II Upgrades

## TL;DR

The paper proposes a CMS detector upgrade that enhances its ability to trigger on low-mass displaced muon pairs, improving sensitivity to exotic particles and other signatures involving displaced vertices.

## Contribution

It introduces a new trigger method enabled by the Phase II upgrade, allowing CMS to detect low-mass displaced muons more effectively than before.

## Key findings

- CMS can trigger on ~1 GeV displaced muon pairs with minimal pT cuts.
- The method improves CMS's competitiveness with LHCb for low-mass exotic searches.
- Applicable to other signatures with MET, H_T, or multiple displaced vertices.

## Abstract

We show that the phase II upgrade of the CMS tracking detector could enable the experiment to trigger on very low mass $\mathcal{O}(1\,\text{GeV})$ displaced muon pairs with minimal $p_T$ cuts. As a result, CMS can be competitive with LHCb when searching for low mass displaced exotics originating from heavy flavor decays. The method can also be applied to signatures without muons but with a moderate amount of MET, $H_T$ or multiple displaced vertices in the event.