Impact of squark generation mixing on the search for squarks decaying into fermions at LHC

TL;DR

This paper investigates how squark generation mixing in the MSSM can lead to significant quark flavor violation signals at the LHC, despite strong experimental constraints, impacting squark searches and parameter determination.

Contribution

It demonstrates that squark generation mixing can produce observable flavor-violating decay signatures at the LHC, challenging previous assumptions about flavor constraints.

Findings

Large branching ratios for squark decays into c-quark + neutralino_1 and t-quark + neutralino_1.

Potential observation of pp -> c t̄ + missing E_T + X signals at LHC.

Significant impact on supersymmetric QFV searches and MSSM parameter analysis.

Abstract

We study the effect of squark generation mixing on squark production and decays at LHC in the Minimal Supersymmetric Standard Model (MSSM). We show that the effect can be very large despite the very strong constraints on quark flavour violation (QFV) from experimental data on B mesons. We find that the two lightest up-type squarks su_{1,2} can have large branching ratios for the decays into 'c-quark + neutralino_1' and 't-quark + neutralino_1' at the same time due to squark generation mixing, leading to QFV signals 'pp -> c bar{t} (t bar{c}) + missing-E_T + X' with a significant rate. The observation of this remarkable signature would provide a powerful test of supersymmetric QFV at LHC. This could have a significant impact on the search for squarks and the determination of the underlying MSSM parameters.