  The hadro-quarkonium picture [S. Dubinskiy and M.B. Voloshin, Phys. Lett. B
666, 344 (2008)] provides one possible interpretation for the pentaquark
candidates with hidden charm, recently reported by the LHCb Collaboration, as
well as for some of the charmonium-like "X,Y,Z" states. In this picture, a
heavy quarkonium core resides within a light hadron giving rise to four- or
five-quark/antiquark bound states. We test this scenario in the heavy quark
limit by investigating the modification of the potential between a static
quark-antiquark pair induced by the presence of a hadron. Our lattice QCD
simulations are performed on a Coordinated Lattice Simulations (CLS) ensemble
with $N_f = 2+1$ flavours of non-perturbatively improved Wilson quarks at a
pion mass of about 223 MeV and a lattice spacing of about 0.0854 fm. We study
the static potential in the presence of a variety of light mesons as well as of
octet and decuplet baryons. In all these cases, the resulting configurations
are favoured energetically. The associated binding energies between the
quarkonium in the heavy quark limit and the light hadron are found to be
smaller than a few MeV, similar in strength to deuterium binding. It needs to
be seen if the small attraction survives in the infinite volume limit and
supports bound states or resonances.
