A&A 390, L31-L34 (2002)
Nucleosynthesis in ray bursts outflowsM. Lemoine
Institut d'Astrophysique de Paris, GReCO, CNRS, 98 bis boulevard Arago, 75014 Paris, France
(Received 1 April 2002 / Accepted 19 June 2002)
It is shown that fusion of neutrons and protons to 4He nuclei occurs in ray burst outflows in a process similar to big-bang nucleosynthesis in the early Universe. Only the surviving free neutrons can then decouple kinematically from the charged fluid so that the multi-GeV neutrino signal predicted from inelastic nuclear n-p collisions is significantly reduced. It is also argued that a sizeable fraction of ultra-high energy cosmic rays accelerated in ray bursts should be 4He nuclei.
Key words: nucleosynthesis - gamma rays: bursts
© ESO 2002