Colored dark matter

We explore the possibility that dark matter (DM) is the lightest hadron made of two stable color octet Dirac fermions Q. The cosmological DM abundance is reproduced for MQ≈12.5 TeV, compatibly with direct searches (the Rayleigh cross section, suppressed by 1/MQ6, is close to present bounds), indirect searches (enhanced by QQ+QQ→QQ+QQ recombination), and with collider searches (where Q manifests as tracks, pair produced via QCD). Hybrid hadrons, made of Q and of standard model quarks and gluons, have large QCD cross sections, and do not reach underground detectors. Their cosmological abundance is 105 times smaller than DM, such that their unusual signals seem compatible with bounds. Those in the Earth and stars sank to their centers; the Earth crust and meteorites later accumulate a secondary abundance, although their present abundance depends on nuclear and geological properties that we cannot compute from first principles.