$$M_W$$ M W , dark matter and $$a_\mu $$ a μ in the NMSSM

Abstract

Abstract We study regions in the parameter space of the NMSSM which are able to simultaneously explain the current measured values for the W mass $$M_W$$ M W and the muon anomalous magnetic moment $$a_\mu $$ a μ , and provide a dark matter relic density consistent with the observations as well as constraints from detection experiments. The corresponding regions feature light charginos and sleptons in the 100 GeV–1 TeV range, at least some of them with masses below 175 GeV such such that the electroweakly-interacting SUSY particles generate sufficiently large contributions to $$M_W$$ M W . The LSP is always singlino-like with a mass below 150 GeV, and could possibly remain invisible even at future detection experiments. Decays of electroweak sparticles proceed through cascades via staus and/or sleptons which makes their detection challenging. We propose benchmark points for future searches of such sparticles. The lightest CP-even scalar may have a mass in the 95–98 GeV range with, however, modest signal rates in view of the mild excesses reported in this range at LEP and by CMS at the LHC.