The CDMS experiment has achieved the world’s most stringent limits on how often dark particles interact with ordinary matter and how heavy they are, in particular in the theoretically favored mass range of more than 40 times the proton mass (about 40 GeV/c2). The regions excluded are those above the solid lines. The black line is the most stringent limit. The bottom axis indicates the WIMP mass and the left axis refers to the frequency with which WIMPs interact with ordinary matter.