Primordial nucleosynthesis and hadronic decay of supersymmetric particles in the early universe Original Research Article

In this talk, we consider the effects on big bang nucleosynthesis (BBN) of the hadronic decay of a long-lived SUSY particle, e.g., gravitino. If high-energy hadrons are emitted near the BBN epoch (t ∼ 10−2 − 102sec), they extraordinarily inter-convert the background nucleons each other even after the freeze-out time of the neutron to proton ratio. Then, produced light element abundances are changed, and that may result in a significant discrepancy between standard BBN and observations. Especially on the theoretical side, now we can obtain a lot of experimental data of hadrons and simulate the hadronic decay process executing the numerical code of the hadron fragmentation even in the high energy region where we have no experimenta data. Using the computed light element abundances in the hadron-injection scenario, we derive a constraint on properties of such a SUSY particle by comparing our theoretical results with observations.