LHC limits on gluinos and squarks in the minimal Dirac gaugino model

Abstract

Abstract Dirac gauginos are a well-motivated extension of the MSSM, leading to interesting phenomenological consequences. At the LHC, gluino-pair production is enhanced while squark production is suppressed as compared to the MSSM, and the decay signatures are altered by a more complex chargino and neutralino spectrum. We investigate how this impacts current gluino and squark mass limits from Run 2 of the LHC. Concretely, we compare different assumptions about the electroweak-ino spectrum through four benchmark models paying particular attention to the effect of the trilinear λ S coupling, which induces a mass splitting between the mostly bino/U(1) adjoint states. Among other results, we show that for large λ S the additional $$ {\tilde{\chi}}_2^0\to f\overline{f}{\tilde{\chi}}_1^0 $$ χ ˜ 2 0 → f f ¯ χ ˜ 1 0 decays somewhat weaken the limits on gluinos (squarks) in case of heavy squarks (gluinos). Moreover, we compare the limits in the gluino vs. squark mass plane to those obtained in equivalent MSSM scenarios.