Probes for 4th generation constituents of dark atoms in Higgs boson
  studies at the LHC
  The nonbaryonic dark matter of the Universe can consist of new stable charged
species, bound in heavy neutral "atoms" by ordinary Coulomb interaction. Stable
$\bar U$ (anti-$U$)quarks of 4th generation, bound in stable colorless ($\bar U
\bar U \bar U $) clusters, are captured by the primordial helium, produced in
Big Bang Nucleosynthesis, thus forming neutral "atoms" of O-helium (OHe), a
specific nuclear interacting dark matter that can provide solution for the
puzzles of direct dark matter searches. However, the existence of the 4th
generation quarks and leptons should influence the production and decay rates
of Higgs boson and is ruled out by the experimental results of the Higgs boson
searches at the LHC, if the Higgs boson coupling to 4th generation fermions
with is not suppressed. Here we argue that the difference between the three
known quark-lepton families and the 4th family can naturally lead to
suppression of this coupling, relating the accelerator test for such a
composite dark matter scenario to the detailed study of the production and
modes of decay of the 125.5 GeV boson, discovered at the LHC.
