1,275 research outputs found
Exotic Solutions to the Solar Neutrino Problem and Some Implications for Low Energy Solar Neutrino Experiments
In this talk, I review, from the phenomenological point of view, solutions to
the solar neutrino problem, which are not provided by the conventional neutrino
oscillation induced by mass and flavor mixing, and show that they can provide a
good fit to the observed data. I also consider some simple implications for low
energy solar neutrino experiments.Comment: Talk presented at International Workshop on Low Energy Solar
Neutrinos (LowNu2), 4-5, December, 2000, Tokyo, Japan, to be published in
Proceedings (World Scientific
Inverted Hierarchy of Neutrino Masses Disfavored by Supernova 1987A
We discuss the flavor conversion of supernova neutrinos in the three-flavor
mixing scheme of neutrinos. We point out that by neutrino observation from
supernova one can discriminate the inverted hierarchy of neutrino masses from
the normal one if s_{13}^2 \gsim a few \times 10^{-4}, irrespective of which
oscillation solution to the solar neutrino problem is realized in nature. We
perform an analysis of data of SN1987A and obtain a strong indication that the
inverted mass hierarchy is disfavored unless s_{13}^2 \lsim a few \times
10^{-4}.Comment: RevTex file, 15 pages, 4 postscript figures, typos corrected, version
to appear in Physics Letters
On the robustness of IceCube's bound on sterile neutrinos in the presence of non-standard interactions
The mixing parameters of sterile neutrino(s) preferred by the MiniBooNE and
LNSD experiments are in strong tension with the exclusion limit from the
IceCube experiment. Recently it has been claimed that by considering the
non-standard neutrino interactions (NSI) in addition to the sterile neutrino,
the IceCube's limit can be relaxed and the tension can be reconciled; a baroque
scenario as it has been called. We will show that this claim is just an
artifact originating from the energy cuts of the chosen datasets. Contrary to
the claim, by turning on the NSI and fixing the NSI parameters to the proposed
values, not only the IceCube's limit on sterile neutrino cannot be alleviated,
but in fact the tension will be aggravated. The reconciliation, more
appropriately, can be called surreal.Comment: 15 pages, 4 figures; v2: a few clarifications have been adde
NOvA and T2K: The race for the neutrino mass hierarchy
The determination of the ordering of the neutrino masses (the hierarchy) is
probably a crucial prerequisite to understand the origin of lepton masses and
mixings and to establish their relationship to the analogous properties in the
quark sector. Here, we follow an alternative strategy to the usual
neutrino--antineutrino comparison in long baseline neutrino oscillation
experiments: we exploit the combination of the neutrino-only data from the NOvA
and the T2K experiments by performing these two off-axis experiments at
different distances but at the same , where is the mean neutrino
energy and is the baseline. This would require a minor adjustment to the
proposed off-axis angle for one or both of the proposed experiments.Comment: 19 pages, 7 figures, LaTE
Long Baseline Neutrino Oscillations: Parameter Degeneracies and JHF/NuMI Complementarity
A summary of the parameter degeneracy issue for long baseline neutrino
oscillations is presented and how a sequence of measurements can be used to
resolve all degeneracies. Next, a comparison of the JHF and NuMI Off-Axis
proposals is made with emphasis on how both experiments running neutrinos can
distinguish between the normal and inverted hierarchies provided the E/L of
NuMI is less than or equal to the E/L of JHF. Due to the space limitations of
this proceedings only an executive style summary can be presented here, but the
references and transparencies of the talk contain the detailed arguments.Comment: 6 pages, Latex, 5 postscript figures. Talk presented by Stephen Parke
at NOON 200
CP and T Violation in Neutrino Oscillations
In this short lecture, we discuss some basic phenomenological aspects of CP
and T violation in neutrino oscillation. Using CP/T trajectory diagrams in the
bi-probability space, we try to sketch out some essential features of the
interplay between the effect of CP/T violating phase and that of the matter in
neutrino oscillation.Comment: 8 pages, 6 figures, Invited talk given by H. Nunokawa at the 10 th
Mexican School of Particles and Fields at Playa del Carmen, Mexico, Oct. 30 -
Nov. 6, 200
CP and T Trajectory Diagrams for a Unified Graphical Representation of Neutrino Oscillations
Recently the CP trajectory diagram was introduced to demonstrate the
difference between the intrinsic CP violating effects to those induced by
matter for neutrino oscillation. In this paper we introduce the T trajectory
diagram. In these diagrams the probability for a given oscillation process is
plotted versus the probability for the CP- or the T-conjugate processes, which
forms an ellipse as the CP or T violating phase is varied. Since the CP and the
T conjugate processes are related by CPT symmetry, even in the presence of
matter, these two trajectory diagrams are closely related with each other and
form a unified description of neutrino oscillations in matter.Comment: 15 pages, Latex, 7 postscript figure
On the Mass Eigenstate Purity of B^8 Solar Neutrinos
We give a brief report on our recent paper, hep-ph/0601198, in which we
calculate the nu_2 mass eigenstate purity of B^8 solar neutrinos as 91 +/- 2 %.Comment: 3 pages, 2 postscript figures, latex, AIP conference style. PANIC
2005 proceeding
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