Search for long-lived particles decaying to jets with displaced vertices in proton-proton collisions at $\sqrt{s} =$ 13 TeV

TL;DR

This paper reports a search for long-lived particles decaying into jets with displaced vertices in proton-proton collisions at 13 TeV, setting new limits on certain supersymmetric particles' masses and decay lengths.

Contribution

It introduces a novel search strategy for long-lived particles with displaced vertices and provides the first constraints on specific supersymmetric models at this energy scale.

Findings

No significant excess observed in data.

Excludes certain long-lived neutralinos, gluinos, and top squarks at 95% confidence level.

Sets limits on cross sections, masses, and decay lengths of long-lived particles.

Abstract

A search is presented for long-lived particles produced in pairs in proton-proton collisions at the LHC operating at a center-of-mass energy of 13 TeV. The data were collected with the CMS detector during the period from 2015 through 2018, and correspond to a total integrated luminosity of 140 fb$^{-1}$. This search targets pairs of long-lived particles with mean proper decay lengths between 0.1 and 100 mm, each of which decays into at least two quarks that hadronize to jets, resulting in a final state with two displaced vertices. No significant excess of events with two displaced vertices is observed. In the context of $R$-parity violating supersymmetry models, the pair production of long-lived neutralinos, gluinos, and top squarks is excluded at 95% confidence level for cross sections larger than 0.08 fb, masses between 800 and 3000 GeV, and mean proper decay lengths between 1 and 25 mm.