Search for millicharged particles in proton-proton collisions at $\sqrt{s} = 13.6$ TeV

TL;DR

This paper reports a search for millicharged particles in proton-proton collisions at 13.6 TeV using the CERN Large Hadron Collider, setting new constraints on particles with very small electric charges and specific mass ranges.

Contribution

It presents the first results from the completed Run 3 milliQan detector, providing the most stringent limits to date on millicharged particles with charges ≤0.24e and masses ≥0.45 GeV.

Findings

Set new upper limits on millicharged particles with charges ≤0.24e.

Achieved the most stringent constraints to date for certain mass and charge ranges.

Utilized the upgraded milliQan detector during Run 3 at the LHC.

Abstract

We report on a search for elementary particles with charges much smaller than the electron charge using a data sample of proton-proton collisions provided by the CERN Large Hadron Collider in 2023--24, corresponding to an integrated luminosity of 124.7~fb$^{-1}$ at a center-of-mass energy of 13.6~TeV. The analysis presented uses the completed Run 3 milliQan bar detector to set the most stringent constraints to date for particles with charges $\leq0.24~\rm{e}$ and masses $\geq0.45~\rm{GeV}$.