  Composite dark matter candidates, which can arise from new strongly-coupled
sectors, are well-motivated and phenomenologically interesting, particularly in
the context of asymmetric generation of the relic density. In this work, we
employ lattice calculations to study the electromagnetic form factors of
electroweak-neutral dark-matter baryons for a three-color, QCD-like theory with
Nf = 2 and 6 degenerate fermions in the fundamental representation. We
calculate the (connected) charge radius and anomalous magnetic moment, both of
which can play a significant role for direct detection of composite dark
matter. We find minimal Nf dependence in these quantities. We generate
mass-dependent cross-sections for dark matter-nucleon interactions and use them
in conjunction with experimental results from XENON100, excluding dark matter
candidates of this type with masses below 10 TeV.
