458 research outputs found
Arguments for a "U.S. Kamioka": SNOLab and its Implications for North American Underground Science Planning
We argue for a cost-effective, long-term North American underground science
strategy based on partnership with Canada and initial construction of a modest
U.S. Stage I laboratory designed to complement SNOLab. We show, by reviewing
the requirements of detectors now in the R&D phase, that SNOLab and a properly
designed U.S. Stage I facility would be capable of meeting the needs of North
America's next wave of underground experiments. We discuss one opportunity for
creating a Stage I laboratory, the Pioneer tunnel in Washington State, a site
that could be developed to provide dedicated, clean, horizontal access. This
unused tunnel, part of the deepest (1040 m) tunnel system in the U.S., would
allow the U.S. to establish, at low risk and low cost, a laboratory at a depth
(2.12 km.w.e., or kilometers of water equivalent) quite similar to that of the
Japanese laboratory Kamioka (2.04 km.w.e.). We describe studies of cosmic ray
attenuation important to properly locating such a laboratory, and the tunnel
improvements that would be required to produce an optimal Stage I facility. We
also discuss possibilities for far-future Stage II (3.62 km.w.e.) and Stage III
(5.00 km.w.e.) developments at the Pioneer tunnel, should future North American
needs for deep space exceed that available at SNOLab.Comment: 23 pages, 10 figures; revised version includes discusion about
neutrino-factory magic baseline
Potential for Precision Measurement of Solar Neutrino Luminosity by HERON
Results are presented for a simulation carried out to test the precision with
which a detector design (HERON) based on a superfluid helium target material
should be able to measure the solar pp and Be7 fluxes. It is found that
precisions of +/- 1.68% and +/- 2.97% for pp and Be7 fluxes, respectively,
should be achievable in a 5-year data sample. The physics motivation to aim for
these precisions is outlined as are the detector design, the methods used in
the simulation and sensitivity to solar orbit eccentricity.Comment: 15 pages, 11 figure
Nuclear Physics Neutrino PreTown Meeting: Summary and Recommendations
In preparation for the nuclear physics Long Range Plan exercise, a group of
104 neutrino physicists met in Seattle September 21-23 to discuss both the
present state of the field and the new opportunities of the next decade. This
report summarizes the conclusions of that meeting and presents its
recommendations. Further information is available at the workshop's web site.
This report will be further reviewed at the upcoming Oakland Town Meeting.Comment: Latex, 31 pages. This version has been updated to include final
Comments from the working group
Solar and Reactor Neutrinos: Upcoming Experiments and Future Projects
Sub-MeV solar neutrino experiments and long-baseline reactor oscillation
experiments toe the cutting edge of neutrino research. The upcoming experiments
KamLAND and BOREXINO, currently in their startup and final construction phase
respectively, will provide essential information on neutrino properties as well
as on solar physics. Future projects, at present under development, will
measure the primary solar neutrino fluxes via electron scattering and neutrino
capture in real time. High precision data for lepton mixing as well as for
stellar evolution theory will become available in the future. This paper aims
to give an overview of the upcoming experiments and of the projects under
development.Comment: 11 pages, 14 figures, LATEX (espcrc2.sty). Contribution to the
proceedings of "TAUP2001 - Topics in Astroparticle and Underground Physics",
LNGS, Italy (September 8-12, 2001
10,000 Standard Solar Models: a Monte Carlo Simulation
We have evolved 10,000 solar models using 21 input parameters that are
randomly drawn for each model from separate probability distributions for every
parameter. We use the results of these models to determine the theoretical
uncertainties in the predicted surface helium abundance, the profile of the
sound speed versus radius, the profile of the density versus radius, the depth
of the solar convective zone, the eight principal solar neutrino fluxes, and
the fractions of nuclear reactions that occur in the CNO cycle or in the three
branches of the p-p chains. We also determine the correlation coefficients of
the neutrino fluxes for use in analysis of solar neutrino oscillations. Our
calculations include the most accurate available input parameters, including
radiative opacity, equation of state, and nuclear cross sections. We
incorporate both the recently determined heavy element abundances recommended
by Asplund, Grevesse & Sauval (2005) and the older (higher) heavy element
abundances recommended by Grevesse & Sauval (1998). We present best-estimates
of many characteristics of the standard solar model for both sets of
recommended heavy element compositions.Comment: ** John N. Bahcall passed away on August 17, 2005. Manuscript has 60
pages including 10 figure
Rayleigh Scattering in Rare Gas Liquids
The Rayleigh scattering length has been calculated for rare-gas liquids in
the ultraviolet for the frequencies at which they luminesce. The calculations
are based on the measured dielectric constants in the gas phase, except in the
case of xenon for which measurements are available in the liquid. The
scattering length mayplace constraints on the design of some large-scale
detectors, using uv luminescence, being proposed to observe solar neutrinos and
dark matter. Rayleigh scattering in mixtures of rare-gas mixtures is also
discussed.Comment: 8 pages, 4 tables; This version corrects erratum in table and has
expanded discussion in Section II. Accepred for publication in NIM
Solar Neutrinos with Three Flavor Mixings
The recent 71Ga solar neutrino observation is combined with the 37Cl and
Kamiokande-II observations in an analysis for neutrino masses and mixings. The
allowed parameter region is found for matter enhanced mixings among all three
neutrino flavors. Distortions of the solar neutrino spectrum unique to three
flavors are possible and may be observed in continuing and next generation
experiments.Comment: August 1992 (Revised) PURD-TH-92-
Solar Neutrinos
Experimental work with solar neutrinos has illuminated the properties of
neutrinos and tested models of how the sun produces its energy. Three
experiments continue to take data, and at least seven are in various stages of
planning or construction. In this review, the current experimental status is
summarized, and future directions explored with a focus on the effects of a
non-zero theta-13 and the interesting possibility of directly testing the
luminosity constraint. Such a confrontation at the few-percent level would
provide a prediction of the solar irradiance tens of thousands of years in the
future for comparison with the present-day irradiance. A model-independent
analysis of existing low-energy data shows good agreement between the neutrino
and electromagnetic luminosities at the +/- 20 % level.Comment: 16 pages, 8 figures. Proceedings of International School on Nuclear
Physics; 27th Course: "Neutrinos in Cosmology, in Astro, Particle and Nuclear
Physics" in Erice, Sicily, Italy; September 16 - 24, 2005. To be published in
Progress Part. Nucl. Phy
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