A Classification of Dark Matter Candidates with Primarily Spin-Dependent Interactions with Matter

Abstract

We perform a model-independent classification of Weakly Interacting Massive Particle (WIMP) dark matter candidates that have the property that their scattering off nucleons is dominated by spin-dependent interactions. We study renormalizable theories where the scattering of dark matter is elastic and arises at tree-level. We show that if the WIMP-nucleon cross section is dominated by spin-dependent interactions the natural dark matter candidates are either Majorana fermions or real vector bosons, so that the dark matter particle is its own anti-particle. In such a scenario, scalar dark matter is disfavored. Dirac fermion and complex vector boson dark matter are also disfavored, except for very specific choices of quantum numbers. We further establish that any such theory must contain either new particles close to the weak scale with Standard Model quantum numbers, or alternatively, a $Z^{\prime }$ gauge boson with mass at or below the TeV scale. In the region of parameter space that is of interest to current direct detection experiments, these particles naturally lie in a mass range that is kinematically accessible to the Large Hadron Collider (LHC).

46 pages, 13 figures, pdflatex. Results extended to the case of complex vector dark matter. References added

References in corpus (9)

• Gauge Singlet Scalars as Cold Dark Matter
• Deducing the nature of dark matter from direct and indirect detection experiments in the absence of collider signatures of new physics
• Model-Independent Jets plus Missing Energy Searches
• Resonant Dark Matter
• Dark Matter candidate in a Heavy Higgs Model - Direct Detection Rates
• Spin Dependence of Dark Matter Scattering
• Dark Matter in the Left Right Twin Higgs Model
• Discriminating dark matter candidates using direct detection
• Direct Detection Constraints on Dark Matter Event Rates in Neutrino Telescopes, and Collider Implications

Cited by in corpus (4)

• The Tevatron at the Frontier of Dark Matter Direct Detection
• Neutral SU(2) Gauge Extension of the Standard Model and a Vector-Boson Dark-Matter Candidate
• Fermion WIMPless Dark Matter at DeepCore and IceCube
• Direct Detection Constraints on Dark Matter Event Rates in Neutrino Telescopes, and Collider Implications