Low-energy phenomenology of superstring-inspired E6 models

The possibility off measuring for the first time neutrino-nuclei coherent scattering has been recently discussed by several experimental collaborations. It is shown that such a measurement may be very sensitive to non-standard interactions of neutrinos with quarks and might set better constraints than those coming from future neutrino factory experiments. We also comment on other types of new physics tests, such as extra heavy neutral gauge bosons, where the sensitivity to some models is slightly better than the Tevatron constraint and, therefore, could give complementary bounds.

https://iopscience.iop.org/article/10.1088/1126-6708/2005/12/021/pdf

Probing new physics with coherent neutrino scattering off nuclei

This paper provides a theoretical framework for the high-precision ({le}1%) electroweak experiments that are likely to be done in the next ten years. The authors have collected the Standard Model (SM) predictions of 14 weak neutral-current observables and 15 {ital W} and {ital Z} properties to the one-loop level and have calculated the deviations that would be caused by ten general types of possible new physics that enter at the tree or loop level. Certain experiments appear to have special promise as probes of the new physics considered here. Most importantly, a systematic procedure is introduced that provides a prescription for the analysis of future experimental data and the means of delineating the nature of new physics if quantitative deviations from SM predictions are observed.

High precision electroweak experiments : a global search for new physics beyond the Standard Model

Evidence for beam polarization has been recently observed in the Large Electron Positron Collider (LEP) at CERN The future of polarized beam experiments in LEP is reviewed The main physics motivations, and foreseeable difficulties, are summarized

Polarization at LEP

Spin effects at supercollider energies

We study various forward-backward and polarization asymmetries evaluated near the Z/sup 0/ resonance for theories with SU(2)/sub L/ x U(1)/sub Y/ x U(1)/sub Y//sub '/ and SU(2)/sub L/ x SU(2)/sub R/ x U(1)/sub B//sub -//sub L/ gauge structures. Extension to other gauge structures is very simple in our formalism. We construct a linear combination of polarized forward-backward asymmetry and polarization asymmetry with initial-state-electron longitudinal polarization whose deviation from the value of the standard model can measure the effects of new currents directly. The analysis is exact at the tree level of the theory and enables one to study any model with any Higgs sector in terms of a fixed number of parameters. The results show that for a typical class of models the measurement of different asymmetries to 1% will impose a lower bound on M/sub Z//sub '/, the mass of an additional neutral gauge boson, to be of order 10 M/sub Z/. Even much less accurate measurements will yield interesting information about new gauge structures. We also examine the implications of extended gauge structures for the precise value of the W/sup +- / mass.

B.W. Lynn

Papers

Gauge structures beyond the standard model and 100-GeV mass region.