On Sat, Jul 6, 2013 at 4:51 PM, <[email protected]> wrote: (The kinetic energy of the original proton has to go > somewhere, so there is more total energy available to the reaction, > probably > resulting in different branching ratios.) >
This point reminds me of some related questions that I've had: - In a system with lots of energy available, are endothermic reactions just as likely as exothermic reactions, all else being equal, provided the energy to be consumed in the reaction in question is sufficiently small (e.g., 0-1 MeV)? Or are exothermic reactions greatly preferred? It seems like nothing but the cross sections would be relevant here, and you could easily have an equilibrium set up between an endothermic and an exothermic reaction if there was enough energy in the system. - Is the cross section of a fusion reaction proportional to the release in energy? Or are the two variables largely independent? Sometimes I see reasoning to the effect that "such and such a branch is preferred over other possible branches because the amount of energy released is large," which seems to imply that the cross section is partly a function of the amount of energy that is released. Eric
