TY - THES
AU - Hayward, Scott Kelly
PY - 1997
TI - Three neutrino oscillations applied to solar and long baseline experiments
KW - Thesis/Dissertation
LA - eng
M3 - Text
AB - Details of the Standard Solar Model and experiments measuring neutrinos produced
inside the sun and in the upper atmosphere are reviewed. Inconsistencies between theoretical
calculations and experimental measurements are discussed, establishing the need
for new physics beyond the Standard Model of Particle Physics.
Neutrino oscillations are introduced as a viable solution and the phenomenology in
the two flavour case is reviewed. Calculations of neutrino oscillations at long baseline experiments
are performed using realistic spectra and source/detector combinations. Both
vacuum and matter enhanced oscillations of solar neutrinos are computed to account for
the solar neutrino data, and allowed regions of parameter space are found.
New analytical results are presented which determine the three family hamiltonian in
matter. Oscillation probabilities in vacuum are calculated, and methods to account for
matter effects are outlined.
A numerical treatment to determine the CKM parameters in matter is shown to be
identical to existing analytical results in the literature. Computer codes developed to calculate
long baseline neutrino oscillation experiments through the earth's variable density
are discussed. Several techniques used in a second set of programs written to determine
solar neutrino survival probabilities in the three neutrino case are also reviewed.
Symmetries between four different mass hierarchies which have two well-separated
mass scales are studied. A two-fold degeneracy noted in the literature is shown to be
inherent in experiments which only measure muon neutrino oscillations, and an expression
relating the two sets of CKM parameters is calculated. Detailed computations illustrate
how long baseline experiments can determine the CKM parameters. First order matter
effects are included and numerical work shows where matter effects are likely to break
some of the symmetries.
The phenomenon of CP violation in both vacuum and matter is studied in the three
neutrino scenario. Existing work on first order matter and CP corrections to oscillation
probabilities at long baseline experiments is extended to second order. It is argued that
since CP effects are very likely to be smaller than matter, second order corrections are
necessary. In detailed calculations, second order effects are clearly apparent. At high
energies the approximation breaks down, but numerical results yield accurate answers
allowing further study. Several strategies to isolate CP violation from competing matter
effects are suggested, including tuning the neutrino beam energy and a novel approach
which combines data sets from accelerator and reactor based experiments. Finally, new
analytical work is presented showing that CP violation may modify the ratio of µ-type
to e-type neutrinos in the atmospheric flux. The magnitude of the effect is estimated
and found to be significant.
New techniques allow solar neutrino survival probabilities to be calculated including
three mixing angles and two mass scales. A preliminary survey is performed assuming
one relevant mass scale but including the three angular parameters. A distinct three
neutrino solution is found by allowing the large neutrino mass squared difference to drop
somewhat below the atmospheric neutrino data's best fit solution of 3 x 10-4 eV². Then
the high energy tail of the 8B neutrino flux is converted to vT by a second resonance
in the sun, leaving unique spectral characteristics to differentiate it from two neutrino
models. [Scientific formulae used in this abstract could not be reproduced.]
N2 - Details of the Standard Solar Model and experiments measuring neutrinos produced
inside the sun and in the upper atmosphere are reviewed. Inconsistencies between theoretical
calculations and experimental measurements are discussed, establishing the need
for new physics beyond the Standard Model of Particle Physics.
Neutrino oscillations are introduced as a viable solution and the phenomenology in
the two flavour case is reviewed. Calculations of neutrino oscillations at long baseline experiments
are performed using realistic spectra and source/detector combinations. Both
vacuum and matter enhanced oscillations of solar neutrinos are computed to account for
the solar neutrino data, and allowed regions of parameter space are found.
New analytical results are presented which determine the three family hamiltonian in
matter. Oscillation probabilities in vacuum are calculated, and methods to account for
matter effects are outlined.
A numerical treatment to determine the CKM parameters in matter is shown to be
identical to existing analytical results in the literature. Computer codes developed to calculate
long baseline neutrino oscillation experiments through the earth's variable density
are discussed. Several techniques used in a second set of programs written to determine
solar neutrino survival probabilities in the three neutrino case are also reviewed.
Symmetries between four different mass hierarchies which have two well-separated
mass scales are studied. A two-fold degeneracy noted in the literature is shown to be
inherent in experiments which only measure muon neutrino oscillations, and an expression
relating the two sets of CKM parameters is calculated. Detailed computations illustrate
how long baseline experiments can determine the CKM parameters. First order matter
effects are included and numerical work shows where matter effects are likely to break
some of the symmetries.
The phenomenon of CP violation in both vacuum and matter is studied in the three
neutrino scenario. Existing work on first order matter and CP corrections to oscillation
probabilities at long baseline experiments is extended to second order. It is argued that
since CP effects are very likely to be smaller than matter, second order corrections are
necessary. In detailed calculations, second order effects are clearly apparent. At high
energies the approximation breaks down, but numerical results yield accurate answers
allowing further study. Several strategies to isolate CP violation from competing matter
effects are suggested, including tuning the neutrino beam energy and a novel approach
which combines data sets from accelerator and reactor based experiments. Finally, new
analytical work is presented showing that CP violation may modify the ratio of µ-type
to e-type neutrinos in the atmospheric flux. The magnitude of the effect is estimated
and found to be significant.
New techniques allow solar neutrino survival probabilities to be calculated including
three mixing angles and two mass scales. A preliminary survey is performed assuming
one relevant mass scale but including the three angular parameters. A distinct three
neutrino solution is found by allowing the large neutrino mass squared difference to drop
somewhat below the atmospheric neutrino data's best fit solution of 3 x 10-4 eV². Then
the high energy tail of the 8B neutrino flux is converted to vT by a second resonance
in the sun, leaving unique spectral characteristics to differentiate it from two neutrino
models. [Scientific formulae used in this abstract could not be reproduced.]
UR - https://open.library.ubc.ca/collections/831/items/1.0085041
ER - End of Reference