General heavy WIMP nucleon elastic scattering

Heavy weakly interacting massive particle (WIMP) effective field theory is used to compute the WIMP-nucleon scattering rate for general heavy electroweak multiplets through order mW/M, where mW and M denote the electroweak and WIMP mass scales. The lightest neutral component of such an electroweak multiplet is a candidate dark matter particle, either elementary or composite. Existing computations for certain representations of electroweak SU(2)W×U(1)Y reveal a cancellation of amplitudes from different effective operators at leading and subleading orders in 1/M, yielding small cross sections that are below current dark matter direct-detection experimental sensitivities. We extend those computations and consider all low-spin (spin-0, spin-1/2, spin-1, spin-3/2) heavy electroweak multiplets with arbitrary SU(2)W×U(1)Y representations and provide benchmark cross section results for dark matter direct detection experiments. For most self-conjugate TeV WIMPs with isospin ≤3 the cross sections are below current experimental limits but within reach of next-generation experiments. An exception is the case of pure electroweak doublet, where WIMPs are hidden below the neutrino floor.