Upper Limits on the Peccei-Quinn Scale and on the Reheating Temperature
  in Axino Dark Matter Scenarios
  Considering axino cold dark matter scenarios with a long-lived charged
slepton, we study constraints on the Peccei-Quinn scale f_a and on the
reheating temperature T_R imposed by the dark matter density and by big bang
nucleosynthesis (BBN). For an axino mass compatible with large-scale structure,
m_axino \gtrsim 100 keV, temperatures above 10^9 GeV become viable for f_a >
3x10^12 GeV. We calculate the slepton lifetime in hadronic axion models. With
the dominant decay mode being two-loop suppressed, this lifetime can be
sufficiently large to allow for primordial bound states leading to catalyzed
BBN of Lithium-6 and Beryllium-9. This implies new upper limits on f_a and on
T_R that depend on quantities which will be probed at the Large Hadron
Collider.
