R-symmetry leads to a distinct low energy realisation of SUSY with a signicantly modified colour-charged sector featuring a Dirac gluino and scalar colour octets (sgluons). In the present work we recast results from LHC BSM searches to discuss the impact of R-symmetry on the squark and gluino mass limits. We work in the framework of the Minimal R-symmetric Supersymmetric Standard Model and take into account the NLO corrections to the squark production cross sections in the MRSSM that have become available recently. We find substantially weaker limits on squark masses compared to the MSSM: for simple scenarios with heavy gluinos and degenerate squarks, the MRSSM mass limit is   <math> <msub> <mi>m</mi> <mover> <mi>g</mi> <mo>˜</mo> </mover> </msub> </math>  $$ {m}_{\tilde{g}} $$  &gt; 1:7TeV, approximately 600 GeV lower than in the MSSM.

Germany

Philip Diessner

Poland

Jan Kalinowski

Wojciech Kotlarski

Dominik Stöckinger

Confronting the coloured sector of the MRSSM with LHC data

The mass of the W boson, M  W , plays a central role for high-precision tests of the electroweak theory. Confronting precise theoretical predictions with the accurately measured experimental value provides a high sensitivity to quantum effects of the theory entering via loop contributions. The currently most accurate prediction for the W boson mass in the Minimal R-symmetric Supersymmetric Standard Model (MRSSM) is presented. Employing the on-shell scheme, it combines all numerically relevant contributions that are known in the Standard Model (SM) in a consistent way with all MRSSM one-loop corrections. Special care is taken in the treatment of the triplet scalar vacuum expectation value v  T  that enters the prediction for M  W  already at lowest order. In the numerical analysis the decoupling properties of the supersymmetric loop contributions and the comparison with the MSSM are investigated. Potentially large numerical effects of the MRSSM-specific Λ superpotential couplings are highlighted. The comparison with existing results in the literature is discussed.

Georg Weiglein

Precise prediction for the W boson mass in the MRSSM

R-symmetry leads to a distinct realisation of SUSY with a significantly modified coloured sector featuring a Dirac gluino and a scalar colour octet (sgluon). We present the impact of R-symmetry on squark production at the 13 TeV LHC. We study the total cross sections and their NLO corrections from all strongly interacting states, their dependence on the Dirac gluino mass and sgluon mass as well as their systematics for selected benchmark points. We find that tree-level cross sections in the R-symmetric model are reduced compared to the MSSM but the NLO K-factors are generally larger in the order of ten to twenty per cent. In the course of this work we derive the required DREG → DRED transition counterterms and necessary on-shell renormalisation constants. The real corrections are treated using FKS subtraction, with results cross checked against an independent calculation employing the two cut phase space slicing method.

Sebastian Liebschner

Squark production in R-symmetric SUSY with Dirac gluinos: NLO corrections

In a recent paper we showed that the Minimal R-symmetric Supersymmetric Standard Model (MRSSM) can accommodate the observed 125 GeV Higgs boson as the lightest scalar of the model in agreement with electroweak precision observables, in particular with the W boson mass and T parameter. Here we explore a scenario with the light singlet (and bino-singlino) state in which the second-lightest scalar takes the role of the SM-like boson with mass close to 125 GeV. In such a case the second-lightest Higgs state gets pushed up via mixing already at tree-level and thereby reducing the required loop correction. Unlike in the NMSSM, the light singlet is necessarily connected with a light neutralino which naturally appears as a promising dark matter candidate. We show that dark matter and LHC searches place further bounds on this scenario and point out parameter regions, which are viable and of interest for LHC Run II and upcoming dark matter experiments.

Exploring the Higgs sector of the MRSSM with a light scalar

We present the impact of two-loop corrections on the mass of the lightest Higgs boson in the minimal R-symmetric supersymmetric standard model (MRSSM). These shift the Higgs boson mass up by typically 5 GeV or more. The dominant corrections arise from strong interactions, and from the gluon and its <math id="M1"><mi>N</mi><mo>=</mo><mn>2</mn></math> superpartners, the sgluon and Dirac gluino, and these corrections further increase with large Dirac gluino mass. The two-loop contributions governed purely by Yukawa couplings and the MRSSM <math id="M2"><mrow><mi>λ</mi></mrow></math>, <math id="M3"><mrow><mi>Λ</mi></mrow></math> parameters are smaller. We also update our earlier analysis which showed that the MRSSM can accommodate the measured Higgs and W boson masses. Including the two-loop corrections increases the parameter space where the theory prediction agrees with the measurement.

Two-Loop Correction to the Higgs Boson Mass in the MRSSM

R-symmetry is a fundamental symmetry which can solve the SUSY flavor problem and relax the search limits on SUSY masses. Here we provide a complete next-to- leading order computation and discussion of the lightest Higgs boson mass, the W boson mass and muon decay in the minimal R-symmetric SUSY model (MRSSM). This model contains non-MSSM particles including a Higgs triplet, Dirac gauginos and higgsinos, and leads to significant new tree-level and one-loop contributions to these observables. We show that the model can accommodate the measured values of the observables for interesting regions of parameter space with stop masses of order 1 TeV in spite of the absence of stop mixing. We characterize these regions and provide typical benchmark points, which are also checked against further experimental constraints. A detailed exposition of the model, its mass matrices and its Feynman rules relevant for computations in this paper is also provided.