Neutrino mixing

Aliani, P. Antonelli, V. Ferrari, R. Picariello, M. Torrente-Lujan, E. Determination of neutrino mixing parameters after SNO oscillation evidence. Physical Review D 2003, 67,013006-1. 

The following values are obtained through data analyses based on the 3-neutrino mixing scheme described in the review Neutrino mass, mixing, and flavor change by B. Kayser in this Review. 

Present experimental evidence and the standard electroweak theory are consistent with the absolute conservation of three separate lepton numbers electron number L, muon number L/j, and tau number Lt, except for the effect of neutrino mixing associated with neutrino masses. Searches for violations are of the following types ... 

Figure 6. Solutions of the gap equations and the charge neutrality condition (solid black line) in the /// vs //, plane. Two branches are shown states with diquark condensation on the upper right (A > 0) and normal quark matter states (A = 0) on the lower left. The plateau in between corresponds to a mixed phase. The lines for the /3-equilibium condition are also shown (solid and dashed straight lines) for different values of the (anti-)neutrino chemical potential. Matter under stellar conditions should fulfill both conditions and therefore for //,( = 0 a 2SC-normal quark matter mixed phase is preferable.

The conceptually simplest way of forming a black hole at the heart of a massive star, thereby setting up the conditions of the hypernova model, is to begin by repudiating the traditional explosion model detonated by neutrinos. The iron core then collapses without remission in the space of one second. A black hole prospers, pulling down the rest of the stellar edifice. This may be a common occurrence for stars of 35 to 40 Mq. However, uncertainties remain concerning convection, mass loss and mixing due to rotation, not to mention the explosion mechanism itself. 

The 0 3 connection has a chiral component that seems to imply that Ti v has a chiral component, or is mixed with the chiral component of the other SU(2) chiral field of the electroweak theory. This is what happens to SU(2) electromagnetism at very high energies. It becomes very similar in formal structure to the theory of weak interactions and has implications for the theory of leptons. The electromagnetic interaction acts on a doublet that can be treated as an element of a Fermi doublet of charged leptons and their neutrinos in the SU(2) theory of the weak interaction. 

There are a number of other interesting limits to be drawn on neutrino properties by somewhat more sophisticated use of the supernova dynamics. Putting another neutrino-antineutrino pair [30], i.e., another two species, into any calculation of the neutron star cooling would probably accelerate this process unacceptably. Further, one can place an upper limit [5] of 45 eV on the mass of any species mixing with the electron neutrino, else no supernova mechanism would succeed, delayed or prompt. 

If further observational and associated theoretical work should confirm the current tension among the SBBN-predicted and observed primordial abundances of D, 4He, 7Li, what physics beyond the standard models of cosmology and particle physics has the potential to resolve the apparent conflicts Are those models which modify the early, radiation-dominated universe expansion rate consistent with observations of the CMB temperature fluctuation spectrum If neutrino degeneracy is invoked, is it consistent with the neutrino properties (masses and mixing angles) inferred from laboratory experiments as well as the solar and cosmic ray neutrino oscallation data ... 

A measurement of CN-cycle neutrino flux (with an expected total flux of about 5 x 108 cm 2 s-1) would test an assumption of the Standard Solar Model that during the early pre-main-sequence Hayashi phase the Sun became homogeneous due to convective mixing and that subsequent evolution has not appreciably altered the distribution of metals [38]. 

See the Particle Listings for a Note Neutrino Mass giving details of neutrinos, masses, mixing, and the status of experimental searches. 

While no direct, uncontested evidence for massive neutrinos or lepton mixing has been obtained, suggestive evidence has come from solar neutrino observations, from anomalies in the relative fractions of Ug and observed in energetic cosmic-ray air showers, and possibly from a Vg appearance experiment at Los Alamos. Sample limits are ... 

Based on experimental data, one can determine the mass difference square (Atr ) and mixing angles (6) for different neutrino transitions. The results are as follows. 

This implies that neutrinos have masses and mix. Furthermore the experimental data show... 

The neutrino mass, mixing, and flavor change are discussed in detail by Kayser in Particle Data Group (2008). 

W boson. This is interpreted as a signature that the weak interaction mixes the quark states. It is sufficient to assume that either the upper or the lower quark states are mixed. The lower quark states are taken to be mixed, and that is indicated by the apostrophes in O Table 10.1 on the symbols of the lower quarks. There is experimental evidence, neutrino oscillations, for the neutrinos also having a tiny little mass (Fukuda and et al. 1998) then of course the lepton states will be mixed as well for the weak interaction (Maid et al. 1962). 

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