Constraints on Supersymmetric Models from Catalytic Primordial   Nucleosynthesis of Beryllium
  The catalysis of nuclear reactions by negatively charged relics leads to increased outputs of primordial ^6Li and ^9Be. In combination with observational constraints on the primordial fractions of ^6Li and ^9Be, this imposes strong restrictions on the primordial abundance and the lifetime of charged relics. We analyze the constraints from the catalysis of ^9Be on supersymmetric models in which the gravitino is the lightest supersymmetric particle and a charged slepton--such as the lighter stau--the next-to-lightest supersymmetric particle (NLSP). Barring the special cases in which the primordial fraction of the slepton NLSP is significantly depleted, we find that the ^9Be data require a slepton NLSP lifetime of less than 6x10^3 seconds. We also address the issue of the catalytic destruction of ^6Li and ^9Be by late forming bound states of protons with negatively charged relics finding that it does not lead to any significant modification of the limit on the slepton lifetime. 
Maxim Pospelov, Josef Pradler and Frank Daniel Steffen