  Searches are performed for resonant and non-resonant Higgs boson pair
production in the $\gamma\gamma b\bar{b}$ final state using 20 fb$^{-1}$ of
proton-proton collisions at a center-of-mass energy of 8 TeV recorded with the
ATLAS detector at the CERN Large Hadron Collider. A 95% confidence level upper
limit on the cross section times branching ratio of non-resonant production is
set at 2.2 pb, while the expected limit is 1.0 pb. The difference derives from
a modest excess of events, corresponding to 2.4 standard deviations from the
background-only hypothesis. The limit observed in the search for a narrow $X
\to hh$ resonance ranges between 0.7 and 3.5 pb as a function of the resonance
mass.
