Search for long-lived particles decaying to jet pairs

TL;DR

This paper reports a search for long-lived particles decaying into jet pairs within specific mass and lifetime ranges, using LHCb data, and sets limits on their production without observing a significant excess.

Contribution

It introduces a novel search for long-lived particles decaying to jet pairs in proton-proton collisions at 7 TeV, focusing on a specific mass and lifetime range, and establishes new limits.

Findings

No significant excess observed above background

Limits set on production cross-section as function of mass and lifetime

Constraints improve understanding of long-lived particle properties

Abstract

A search is presented for long-lived particles with a mass between 25 and 50 GeV$/c^2$ and a lifetime between 1 and 200 ps in a sample of proton-proton collisions at a centre-of-mass energy of $\sqrt{s}=7$ TeV, corresponding to an integrated luminosity of 0.62 fb$^{-1}$, collected by the LHCb detector. The particles are assumed to be pair-produced by the decay of a Standard Model-like Higgs boson. The experimental signature of the long-lived particle is a displaced vertex with two associated jets. No excess above the background is observed and limits are set on the production cross-section as a function of the long-lived particle mass and lifetime.