text: From Eq. (19), one can see that σ(p)  (sin 2θ/v′)2 for a given DM mass mN . Fig. 3 shows 
  SI ∝ 
  
  the spin-independent cross section of RH neutrino with a proton. The resultant cross section 
  
  is found to be far below the current limits reported by XENON10 [24] and CDMSII [25]: 
  
  8 
  7 pb, for a DM mass of 100 GeV-1 TeV. Future experiments such  σSI . 4  10−  2  10− 
  ×  −  × 
  
  as XENON1T [26] can reach the cross section predicted in our model. 
  
  10-8 