Color-octet scalars in Dirac gaugino models with broken <em>R</em> symmetry

In this work we study the collider phenomenology of color-octet scalars (<em>sgluons</em>) in supersymmetric models with Dirac gaugino masses that feature an explicitly broken <em>R</em> symmetry (<em>R</em>-<em>broken models</em>). We construct such models by augmenting minimal <em>R</em>-symmetric models with a fairly general set of supersymmetric and softly supersymmetry-breaking operators that explicitly break <em>R</em> symmetry. We then compute the rates of all significant two-body decays and highlight new features that appear as a result of <em>R</em> symmetry breaking, including enhancements to extant decay rates, novel tree- and loop-level decays, and improved cross sections of single sgluon production. We demonstrate in some detail how the familiar results from minimal <em>R</em>-symmetric models can be obtained by restoring <em>R</em> symmetry. In parallel to this discussion, we explore constraints on these models from the Large Hadron Collider. We find that, in general, <em>R</em> symmetry breaking quantitatively affects existing limits on color-octet scalars, perhaps closing loopholes for light CP-odd (pseudoscalar) sgluons while opening one for a light CP-even (scalar) particle. Qualitatively, however, we find that — much as for minimal <em>R</em>-symmetric models, despite stark differences in phenomenology — scenarios with broken <em>R</em> symmetry and two sgluons below the TeV scale can be accommodated by existing searches.