10 research outputs found
Supernova Bounds on Majoron-emitting decays of light neutrinos
Neutrino masses arising from the spontaneous violation of ungauged
lepton-number are accompanied by a physical Goldstone boson, generically called
Majoron. In the high-density supernova medium the effects of Majoron-emitting
neutrino decays are important even if they are suppressed in vacuo by small
neutrino masses and/or small off-diagonal couplings. We reconsider the
influence of these decays on the neutrino signal of supernovae in the light of
recent Super-Kamiokande data on solar and atmospheric neutrinos. We find that
majoron-neutrino coupling constants in the range 3\times 10^{-7}\lsim g\lsim
2\times 10^{-5} or g \gsim 3 \times 10^{-4} are excluded by the observation
of SN1987A. Then we discuss the potential of Superkamiokande and the Sudbury
Neutrino Observatory to detect majoron neutrino interactions in the case of a
future galactic supernova. We find that these experiments could probe majoron
neutrino interactions with improved sensitivity.Comment: 28 pages, 5 figure
Next-to-Leading Order QCD Analysis of Polarized Deep Inelastic Scattering Data
We present a Next-to-Leading order perturbative QCD analysis of world data on
the spin dependent structure functions , and , including
the new experimental information on the dependence of . Careful
attention is paid to the experimental and theoretical uncertainties. The data
constrain the first moments of the polarized valence quark distributions, but
only qualitatively constrain the polarized sea quark and gluon distributions.
The NLO results are used to determine the dependence of the ratio
and evolve the experimental data to a constant . We
determine the first moments of the polarized structure functions of the proton
and neutron and find agreement with the Bjorken sum rule.Comment: 21 pages, 4 figures; final version to be published in Phys. Lett. B.
References updated. Uses elsart.cls version 1996/04/22, 2e-1.4
Soft computing in absorption cooling systems
Absorption cooling systems make sense in many applications for process water cooling. Instead of mechanically compressing a refrigerant gas, as in the conventional vapor compression process, absorption cooling uses a thermo-chemical process. Two different fluids are used, a refrigerant and an absorbent. Heat directly from natural gas combustion, solar energy, waste-heat source or indirectly from a boiler, drives the process.
In recent years, soft computing (SC) methods have been widely utilized in the analysis of absorption cooling systems. Soft computing is becoming useful as an alternate approach to conventional techniques. Soft computing differs from conventional (hard) computing in that, unlike hard computing, it is tolerant of imprecision, uncertainty, partial truth, and approximation.
In this chapter, the research of applying soft computing methods for absorption cooling applications is presente
Λ0 polarization in Z0 decays at LEP
The longitudinal polarization of the Λb baryon is measured at the LEP e+e- collider by DELPHI. It is determined from b the charged lepton and neutrino energy spectra in 249±19 Λb semileptonic decays reconstructed in ≈3.5 million hadronic b Z0 decays using Λ0-lepton correlations. The measured polarization is: PΛb = -49q±0.32 -30(stat)±0.17(syst.)0info:eu-repo/semantics/publishe