Big-bang nucleosynthesis with sub-GeV massive decaying particles
  We consider the effects of the injections of energetic photon and electron
(or positron) on the big-bang nucleosynthesis. We study the photodissociation
of light elements in the early Universe paying particular attention to the case
that the injection energy is sub-GeV and derive upper bounds on the primordial
abundances of the massive decaying particle as a function of its lifetime. We
also discuss a solution of the $^7$Li problem in this framework.
