摘要:

The LSND and KARMEN &ngr; oscillation experiments are compared in order to clarify the significance of the apparent disagreement between their results. ©1999 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.59456

出版商:AIP    

年代:1999

数据来源: AIP

摘要:

Implications of the oscillation interpretations of solar, atmospheric, and LSND neutrino data are discussed. We list many open questions, and point out the promise of future data to answer these. Two issues discussed in some detail are (i) the difficult nature of measuring CP-violation in oscillations, and (ii) the promise of reconstructing the flavor-basis neutrino mass matrix from oscillation data. ©1999 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.59423

出版商:AIP    

年代:1999

数据来源: AIP

摘要:

©1999 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.59425

出版商:AIP    

年代:1999

数据来源: AIP

摘要:

A simultaneous understanding of the results of the LSND experiment indicating&ngr;&mgr;−&ngr;eoscillation together with other evidences for neutrino oscillations from solar and atmospheric neutrino data seems to require the existence of at least one sterile neutrino. One can also give other plausible astrophysical arguments that seem to require light sterile neutrinos. If such sterile neutrinos exist, a major theoretical challenge is to understand why they are so light. A scenario for the light sterile neutrino is presented where one assumes a parity doubling of the standard model with identical matter and gauge content. The neutrinos of the parity doubled (mirror) sector are light for the same reason that the known neutrinos are light and since they do not couple to the known W and Z bosons, they can be identified with the sterile neutrinos. Some of the implications and possible tests of this hypothesis are mentioned. ©1999 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.59426

出版商:AIP    

年代:1999

数据来源: AIP

摘要:

The existence of small mixings between light active and sterile neutrino species could have implications for Big Bang and Supernova Heavy Element Nucleosynthesis. As well, such mixing would force us to abandon cherished constraints on light neutrino Dark Matter. Two proposed 4-neutrino mass and mixing schemes, for example, can both accomodate existing experimental results and lead to elegant solutions to the neutron-deficit problem forr-Process nucleosynthesis from neutrino-heated supernova ejecta. Each of these solutions is based on matter-enhanced (MSW) active-sterile neutrino transformation. In plausible extensions of these schemes to the early universe, Shi & Fuller have shown that relatively light mass (∼200 eV to ∼10 keV) sterile neutrinos produced via active-sterile MSW conversion can have a “cold” energy spectrum. Neutrinos produced in this way circumvent the principal problem of light neutrino dark matter and would be, essentially, Cold Dark Matter. ©1999 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.59427

出版商:AIP    

年代:1999

数据来源: AIP

摘要:

Probably the most promising way of detecting cosmic neutrinos is measuring the mechanical force exerted by elastic scattering of cosmic neutrinos from macroscopic targets. The expected acceleration is∼10−23&hthinsp;cm/s2for Dirac neutrinos of mass ∼10 eV and local density∼107/cm3.A novel torsion balance design is presented, which addresses the sensitivity-limiting factors of existing balances, such as seismic and thermal noise, and angular readout resolution and stability. ©1999 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.59428

出版商:AIP    

年代:1999

数据来源: AIP

摘要:

We review recent results on the connection between the see-saw mechanism and supersymmetry. It is shown that spontaneously broken B–L symmetry, in theories with a renormalizable see-saw, determines completely the low energy structure of the supersymmetric Standard Model: it implies exact R-parity. We then discuss how the violation of the survival principle in supersymmetric SO(10) naturally leads to an intermediate see-saw scale and the lowering of the unification scale. This affects the predictions for proton decay:p→&pgr;0e+may be the dominant mode. ©1999 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.59429

出版商:AIP    

年代:1999

数据来源: AIP