9,938 research outputs found
Solar Neutrinos Before and After Neutrino 2004
We compare, using a three neutrino analysis, the allowed neutrino oscillation
parameters and solar neutrino fluxes determined by the experimental data
available Before and After Neutrino 2004. New data available after Neutrino2004
include refined KamLAND and gallium measurements. We use six different
approaches to analyzing the KamLAND data. We present detailed results using all
the available neutrino and anti-neutrino data for Delta m^2_{12}, tan^2
theta_{12}, sin^2 theta_{13}, and sin^2 eta (sterile fraction). Using the same
complete data sets, we also present Before and After determinations of all the
solar neutrino fluxes, which are treated as free parameters, an upper limit to
the luminosity fraction associated with CNO neutrinos, and the predicted rate
for a 7Be solar neutrino experiment. The 1 sigma (3 sigma) allowed range of
Delta m^2_{21} = (8.2 +- 0.3) (^+1.0_-0.8)times 10^{-5} eV^2 is decreased by a
factor of 1.7 (5), but the allowed ranges of all other neutrino oscillation
parameters and neutrino fluxes are not significantly changed. Maximal mixing is
disfavored at 5.8 sigma and the bound on the mixing angle theta_{13} is
slightly improved to sin^2 theta_{13}<0.048 at 3 sigma. The predicted rate in a
7Be neutrino-electron scattering experiment is (0.665 +-0.015) of the rate
implied by the BP04 solar model in the absence of neutrino oscillations. The
corresponding predictions for p-p and pep experiments are, respectively, 0.707
{+0.011}{-0.013} and 0.644 {+0.011}{-0.013}. We derive upper limits to CPT
violation in the weak sector by comparing reactor anti-neutrino oscillation
parameters with neutrino oscillation parameters. We also show that the recent
data disfavor at 91 % CL a proposed non-standard interaction description of
solar neutrino oscillations.Comment: Added predictions for p-p and pep neutrino-electron scattering rate;
publishe
Global Analysis of Solar Neutrino Oscillations Including SNO CC Measurement
For active and sterile neutrinos, we present the globally allowed solutions
for two neutrino oscillations. We include the SNO CC measurement and all other
relevant solar neutrino and reactor data. Five active neutrino oscillation
solutions (LMA, LOW, SMA, VAC, and Just So2) are currently allowed at 3 sigma;
three sterile neutrino solutions (Just So2, SMA, and VAC) are allowed at 3
sigma. The goodness of fit is satisfactory for all eight solutions. We also
investigate the robustness of the allowed solutions by carrying out global
analyses with and without: 1) imposing solar model constraints on the 8B
neutrino flux, 2) including the Super-Kamiokande spectral energy distribution
and day-night data, 3) including a continuous mixture of active and sterile
neutrinos, 4) using an enhanced CC cross section for deuterium (due to
radiative corrections), and 5) a optimistic, hypothetical reduction by a factor
of three of the error of the SNO CC rate. For every analysis strategy used in
this paper, the most favored solutions all involve large mixing angles: LMA,
LOW, or VAC. The favored solutions are robust, but the presence at 3 sigma of
individual sterile solutions and the active Just So2 solution is sensitive to
the analysis assumptions.Comment: 9 figures, higher resolution versions at http://www.sns.ias.edu/~jnb,
added references and clarification
Flat glass or crystal dome aperture? A year-long comparative analysis of the performance of light pipes in real residential settings and climatic conditions
This paper presents the first comparative study of its type of the performance of light pipes with different types of apertures: a flat glass versus a bohemian crystal dome. Measurements were taken at 20-minute intervals over a period of one year in the bathrooms of two newly built identical houses of the same orientation located in Manchester, UK. The comparative analysis of the data collected for both light pipes types reveals that the crystal domed aperture consistently outperforms the flat glass one. Furthermore, the difference in the recorded horizontal illuminance is most marked during the winter months and at the end of the one-year experiment, indicating that the crystal dome has better performance for low incident winter light and higher resistance for the long term effect of weathering and pollution. This study provides strong evidence based on long term real measurements. Such evidence informs architects’ decisions when weighing up the aesthetic considerations of a flat glass aperture versus the higher illumination levels afforded by a crystal dome aperture with higher resistance to weathering and pollution
Recent results on self-dual configurations on the torus
We review the recent progress on our understanding of self-dual SU(N)
Yang-Mills configurations on the torus.Comment: Latex 3 pages, 1 figure. Contribution to the Lat99 Proceeding
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