A. Spin Independent c$_{q}$ = y$_{q}$ y$_{χ}$ 1 m 2 h , (9) σ$_{SI}$ ( χ N → χ N ) = 4 π m 2 r 1 A 2 ( Z f$_{p}$ + ( A − Z ) f$_{n}$ ) $^{2}$, (8) f ( p ) Tu = 0 . 023 f ( p ) Td = 0 . 034 f ( p ) Ts = 0 . 14 f ( p ) TG = 0 . 803 f ( n ) Tu = 0 . 019 f ( n ) Td = 0 . 041 f ( n ) Ts = 0 . 14 f ( n ) TG = 0 . 800 . f$_{N}$ m$_{N}$ = ∑ q = u,d,s f ( N ) Tq 1 m$_{q}$ c$_{q}$ + 2 27 f ( N ) TG ∑ q = c,b,t 1 m$_{q}$ c ( h ) q , (7) 〈 N | m$_{q}$ ¯ q q | N 〉 = m$_{N}$ f ( N ) Tq , (6) O SI q = c$_{q}$ (¯ χ χ ) (¯ q q ) , (5) The operator responsible for SI DM-nucleus interactions is where χ is the DM and q is a quark. Taking the expectation value of this operator between two nucleon states ( N = p (proton) or n (neutron)) determines the effective interaction of the DM with a nucleon, where the nuclear matrix element f ( N ) Tq is determined in chiral perturbation theory from the pion nucleon-scattering sigma term. The coefficient of the effective DM-nucleon interaction, f$_{N}$ (¯ χ χ )( ¯ N N ), is given by where f ( N ) TG = 1 − ∑ q = $_{u,d,s}$f ( N ) Tq and the h on c ( h ) q refers to Higgs boson exchange [31]. The nucleon-Higgs interaction is coherent over the nucleus [32] resulting in the well known A 2 enhancement for SI cross sections. To compare between experiments using different nuclei, the elastic scattering cross section is normalized to a per nucleon value [13]: where m$_{r}$ is the reduced mass between the DM and a nucleon. We use the DarkSUSY package for numerical analysis [33], so for analytic estimates we will use the same values for the nuclear matrix elements, namely Since these values are derived from the pion nucleon scattering sigma term, their error bars are correlated. If the Higgs boson, h , that mediates the interaction between the DM and the nucleon is SM-like, the coefficients c$_{q}$ are given by 6