3,569 research outputs found
Electron-spin beat susceptibility of excitons in semiconductor quantum wells
Recent time-resolved differential transmission and Faraday rotation
measurements of long-lived electron spin coherence in quantum wells displayed
intriguing parametric dependencies. For their understanding we formulate a
microscopic theory of the optical response of a gas of optically incoherent
excitons whose constituent electrons retain spin coherence, under a weak
magnetic field applied in the quantum well's plane. We define a spin beat
susceptibility and evaluate it in linear order of the exciton density. Our
results explain the many-body physics underlying the basic features observed in
the experimental measurements
Relations between the SNO and the Super Kamiokande solar neutrino rates
By comparing the neutrino spectra measured by SNO and Super Kamiokande, we
obtain inequalities between the ratios of observed rate to SSM rate for the two
experiments. These inequalities apply to a possibly energy-dependent reduction
of the SSM flux and to the case of neutrino oscillations. We use them to
examine the relationship between the two experiments expected for the MSW and
``Just-So" oscillation scenarios.Comment: 8 pages + 3 figures, REVTeX, uuencoded file created on a VMS syste
Solar neutrino interactions: Using charged currents at SNO to tell neutral currents at Super-Kamiokande
In the presence of flavor oscillations, muon and tau neutrinos can contribute
to the Super-Kamiokande (SK) solar neutrino signal through the neutral current
process \nu_{\mu,\tau} e^{-}\to \nu_{\mu,\tau} e^{-}. We show how to separate
the \nu_e and \nu_{\mu,\tau} event rates in SK in a model independent way, by
using the rate of the charged current process \nu_e d \to p p e^{-} from the
Sudbury Neutrino Observatory (SNO) experiment, with an appropriate choice of
the SK and SNO energy thresholds. Under the additional hypothesis of no
oscillations into sterile states, we also show how to determine the absolute
^{8}B neutrino flux from the same data set, independently of the \nu_e survival
probability.Comment: 14 pages (RevTeX), incl. 3 figures (epsf), submitted to Phys. ReV.
A Market Approach to Managing Solid and Hazardous Waste: Waste Exchange Clearinghouses in the United States and the European Community
A Market Approach to Managing Solid and Hazardous Waste: Waste Exchange Clearinghouses in the United States and the European Community
A Market Approach to Managing Solid and Hazardous Waste: Waste Exchange Clearinghouses in the United States and the European Community
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