>There is also a competing reaction: He3 + p => He4 + neutrino + beta+ (or maybe e- capture) (weak force mediated decay).<
I would not expect to see He4 formed directly by the proton addition to He3 because the binding energy would tear it apart unless it is released quickly. Every viable fusion reaction that has He4 as a final product releases one or more large nucleons(proton, neutron or alpha) that help carry away the binding energy. Dave -----Original Message----- From: mixent <[email protected]> To: vortex-l <[email protected]> Sent: Mon, Jul 23, 2012 12:01 am Subject: Re: [Vo]:principles of DGTG 's technology In reply to Eric Walker's message of Sun, 22 Jul 2012 19:16:36 -0700: i, snip] On Sun, Jul 22, 2012 at 3:16 PM, <[email protected]> wrote: Unfortunately AFAIK, all the energy of the p-e-p reaction is carried by the neutrino which of course escapes, hence no net measurable energy effect. :( > Yes, indeed. For the following calculation, I'm getting exactly 1.44 MeV, the amount thought to be carried off by the neutrino: ((2*(mass proton)+(mass electron)) - (mass deuteron))*c^2 Some interesting points to note, however: - This would then get you deuterium, which would allow the the proton-proton chain to continue to 3He and beyond. - 1.44 MeV is not all that big in comparison to 26.73 MeV, the energy for the full chain. - According to the article, the ratio of pep to pp is 1:400. But if the resulting diproton takes billions of years to beta+ decay, Slight misunderstanding here. The Diproton doesn't exist. It falls apart mmediately into two protons. The only time you get D is when the conversion of proton to a neutron just happens to occur during the very brief instant in ime that the diproton exists. It's because this combination of events is so xtremely unlikely that the half-life of the reaction is so large. >I assume pep result, D, would dominate. - There might be a parameter such as magnetism that influences this and subsequent steps in the proton-proton chain that we don't fully understand. I'm probably neglecting an important detail, here. Eric BTW the remainder of the pp reaction chain looks like this:- D+p => He3 (Plenty of p around for every D formed, so this reaction happens very uickly - days). (no weak force required). He3 + He3 => He4 + 2 p (also no weak force required). There is also a competing reaction: He3 + p => He4 + neutrino + beta+ (or maybe e- capture) (weak force mediated ecay). Because He3 would be relatively scarce in the early life of a star, I would xpect the second reaction to dominate initially, but probably not for very ong, as there is something like 26 orders of magnitude difference in the eaction rates between the two. egards, Robin van Spaandonk http://rvanspaa.freehostia.com/project.html
