In reply to Axil Axil's message of Sun, 20 May 2018 15:10:28 -0400: Hi, [snip] > The proton proton (PP) fusion reaction is the most enigmatic nuclear >reaction that you will ever run across. This reaction has concerned me a >lot and still confuses me. > >https://en.wikipedia.org/wi... > >Protonproton chain reaction > > > >The PP reaction should not occur, but it is said to occur as the power >source of the Sun as well as all the other stars because there is so much >hydrogen involved in the energy cycle of the Sun. > >"In the Sun, deuterium-producing events are rare. Diprotons are the much >more common result of protonproton reactions within the star, and >diprotons almost immediately decay back into two protons. Since the >conversion of hydrogen to helium is slow, the complete conversion of the >hydrogen in the core of the Sun is calculated to take more than 10^10 (ten >billion) years." > >The PP reaction should be impossible to happen here on earth, but there is >evidence that helium is being generated in all sorts of LENR systems. Why >does LENR make PP fusion possible or possible very likely to occur?
The PP reaction probably doesn't happen here on Earth. The neutron in Deuterium is quite heavy compared to the neutrons in other nuclei. In short, when a proton converts to a neutron inside another nucleus much less energy has to be found, so it can happen much faster. IMO that's why the half lives of beta+ decay reactions for isotopes heavier that D are much shorter than for the PP reaction. [snip] Regards, Robin van Spaandonk local asymmetry = temporary success