L. Labzowsky (1,2), D. Solovyev (1) and T. Zalialiutdinov (1) ((1) V. A. Fock Institute of Physics, St. Petersburg State University,
Petrodvorets, Oulianovskaya, St. Petersburg, Russia (2) Petersburg Nuclear Physics Institute, 188300, Gatchina, St. Petersburg, Russia)
QED theory of multiphoton cascade transitions in atoms and ions is developed. This theory allows for the accurate description of the process important for astrophysical studies of the cosmological hydrogen recombination. In particular the 3s→1s+2γ, 4s→1s+2γ and 3p→1s+3γ processes are considered and some controversies existing in the literature are resolved.
Complete preprint ==> http://arxiv.org/abs/1204.2364