We have studied Electroweak Symmetry Breaking ( EWSB ) fine-tuning in the context of two unified Supersymmetry scenarios : the Constrained Minimal Supersymmetric Model ( CMSSM ) and models with Non-Universal Higgs Masses ( NUHM ) , in light of current and upcoming direct detection dark matter experiments .
We consider both those models that satisfy a one-sided bound on the relic density of neutralinos , \Omega _ { \tilde { \chi } ^ { 0 } _ { 1 } } h ^ { 2 } < 0.12 , and also the subset that satisfy the two-sided bound in which the relic density is within the 2 sigma best fit of WMAP7 + BAO + H0 data .
We find that current direct searches for dark matter probe the least fine-tuned regions of parameter-space , or equivalently those of lowest \mu , and will tend to probe progressively more and more fine-tuned models , though the trend is more pronounced in the CMSSM than in the NUHM .
Additionally , we examine several subsets of model points , categorized by common mass hierarchies ; M _ { \tilde { \chi } ^ { 0 } _ { 1 } } \sim M _ { \tilde { \chi } ^ { \pm } _ { 1 } } ,M _ { \tilde { \chi } ^ { 0 } _ { 1 % } } \sim M _ { \tilde { \tau } _ { 1 } } ,M _ { \tilde { \chi } ^ { 0 } _ { 1 } } \sim M _ { \tilde { t } _ { 1 } } , the light and heavy Higgs poles , and any additional models classified as “ other ” ; the relevance of these mass hierarchies is their connection to the preferred neutralino annihilation channel that determines the relic abundance .
For each of these subsets of models we investigated the degree of fine-tuning and discoverability in current and next generation direct detection experiments .