Search for Squarks in R-parity Violating Supersymmetry in ep Collisions at HERA

TL;DR

This paper reports a search for squarks in R-parity violating supersymmetry at HERA, analyzing the full dataset to set limits on squark masses and couplings, with no evidence of their production found.

Contribution

First comprehensive search for squarks via R-parity violation at HERA, establishing new mass limits within supersymmetric models.

Findings

No evidence for squark production was observed.

Squarks with masses up to 275 GeV are excluded at 95% confidence for lambda'=0.3.

Down-type squarks are excluded up to 290 GeV.

Abstract

A search for squarks in R-parity violating supersymmetry is performed in e^+- p collisions at HERA using the H1 detector. The full data sample taken at a centre-of-mass energy sqrt{s}=319 GeV is used for the analysis, corresponding to an integrated luminosity of 255 pb^-1 of e^+ p and 183 pb^-1 of e^- p collision data. The resonant production of squarks via a Yukawa coupling lambda' is considered, taking into account direct and indirect R-parity violating decay modes. Final states with jets and leptons are investigated. No evidence for squark production is found and mass dependent limits on lambda' are obtained in the framework of the Minimal Supersymmetric Standard Model and in the Minimal Supergravity Model. In the considered part of the parameter space, for a Yukawa coupling of electromagnetic strength lambda'= 0.3, squarks of all flavours are excluded up to masses of 275 GeV at 95% confidence level, with down-type squarks further excluded up to masses of 290 GeV.