Late Energy Injection and Cosmological Constraints in Axino Dark Matter
  Scenarios
  Taking into account effects of late energy injection, we examine big bang
nucleosynthesis (BBN) constraints on axino dark matter scenarios with
long-lived charged sleptons. We calculate 4-body slepton decays into the axino,
a lepton, and a quark-antiquark pair since they govern late hadronic energy
injection and associated BBN constraints. For supersymmetric hadronic axion
models, we present the obtained hadronic BBN constraints and show that they can
be more restrictive than the ones associated with catalyzed BBN via
slepton-bound-state formation. From the BBN constraints on hadronic and
electromagnetic energy release, we find new upper limits on the Peccei-Quinn
scale.
