Wednesday 14 July 2010

Further Solar Neutrino Mysteries

Scientists have known how the Sun shines for quite a while, thermonuclear fusion was well established as was the so called proton proton chain, in which four protons, from hydrogen atoms are converted into Helium nuclei,2 neutrinos and two positrons. Since neutrinos react rarely enough to mostly pass through all the sun, it would be possible to measure the rate of thermonuclear fusion in the sun, by how many neutrino where captured in a lab on earth. Yet when the homestake experiment first measured the number of neutrinos they found only third of the amount expected. Later experiments confirmed this, and it turned out that neutrinos could change the flavour, or type of neutrino from ones with react with atoms, to one which can't. While the sun create only electron type anti neutrinos, by the time the react with an detector on earth, they become an equal mix of electron, muon and tau anti-neutrinos. Since only the electron type reacts with atoms, the rate observed is just one third of the amount predicted by the sun being powered by fusion. Mystery solved and everything ok again, except...


Just published on ArXiv, C.R. Das and J. Pulido find a much better fit to measurements amount of neutrinos coming from the sun, if as well as oscillating, some of them also decay. The paper is a possible indication of non standard interactions.


I can't help but relate this to my own, axial force theory. It something of an oversight but so far, I've only done the briefest of calculation of cross-sections for high-speed neutrino, due to the axial force, noting that effect falls over as 1/E^2 for ultra relativistic neutrino we can detect from the sun, any effect would be small. However, extra scattering it is at least of the right sign, to remove some of the extra electron neutrinos. In addition the axial force can allow neutrinos to decay from one form to another (but only in the presence of other matter), to some degree. So plenty of calculations for me to do.