In reply to Jones Beene's message of Sat, 23 Mar 2013 17:29:00 -0700: Hi, [snip] > > >-----Original Message----- >From: mix...@bigpond.com > >> What makes you think it would require several MeV? Last I saw, they were >having trouble proving that the neutrino had any mass at all, let alone >several MeV. > >What you must be referring to is rest mass; but like a photon, neutrinos >always move very close to the speed of light. When a neutron decays, on rare >occasion, the proton and electron stay bound, and the electron anti-neutrino >carries away all the energy which is ~.78 MeV. This is generally assumed to >represent the upper limit of mass-energy of the electron anti-neutrino. It >is reasonable to assume if pair production is involved it would be require >over 1.5 MeV.
It is not at all reasonable. In fact quite the reverse. If you look at the other end of the neutron decay spectrum, you will see that the maximum energy acquired by the electron is 782 keV, which is apparently available, while the anti-neutrino is still formed, implying that formation of a low energy anti-neutrino requires next to no energy. In this respect, I suspect that neutrinos are much like photons. They can carry almost any amount of energy, including near zero. > >Of course, the next little problem is that there is no evidence at all for >neutrino pair production, ergo ... another putative miracle is required. How do you know that beta decay is not evidence for neutrino anti-neutrino pair production? Regards, Robin van Spaandonk http://rvanspaa.freehostia.com/project.html
