Confronting the coloured sector of the MRSSM with LHC data

Abstract

R-symmetry leads to a distinct low energy realisation of SUSY with a significantly 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 mq > 1.7 TeV, approximately 600 GeV lower than in the MSSM.

Exploring color-octet scalar parameter space in minimal R-symmetric models

“…The fifth and sixth benchmarks, B5 and B6, are less conservative than the first four. B5 closely approaches even the relaxed R-symmetric stop and gluino mass limits [8], and B6 is a unique benchmark in which we abandon the natural hierarchy between Dirac gauginos and scalars. Unmentioned in table 2 are scenarios where we probe the mass splitting of the stops.…”

“…Another is the suppression of squark pair production due to vanishing amplitudes of certain processes, such as q L q L →q LqL via t-channel JHEP11(2020)024 gluino [4,5]. For these and other reasons, the parameter space of R-symmetric models remains far less constrained by searches for colored particles than that of the MSSM [6][7][8].…”

Color-octet scalars in Dirac gaugino models with broken R symmetry

“…Notable among these are an elegant cancellation of quadratic divergences in loop contributions to scalar masses (supersoftness); a natural hierarchy between these masses and those of the gauginos; the suppression of squark pair production (supersafeness) due to vanishing amplitudes of certain processes, such as q L q L →q LqL via t-channel gluino [20,21]; and the appearance of new complex adjoint scalars. The abundant particle content and rich phenomenology of minimal R-symmetric modelsboth markedly different from those of the MSSM -leave the parameter space of the former far less constrained than that of the latter [22][23][24]. These models have provided a vast new terrain for phenomenological exploration at the LHC .…”

Mixed gluinos and sgluons from a new SU(3) gauge group

“…The collider phenomenology of colorons, Dirac and mixed Majorana/Dirac gluinos, and sgluons has already been the subject of many papers, see refs. [9, 12-18, 21, 22, 65, 66], and [67][68][69][70][71][72][73], and [74][75][76][77][78][79], respectively. A detailed discussion of the LHC phenomenology is beyond the scope of the present paper, but a few brief comments are in order, with emphasis on qualitative issues where the model described above differs from the situation encountered in previous studies based on pure Dirac gluinos from supersoft and and hybrid models with an N = 2 gauge sector.…”