C4. Commission on Cosmic Rays

Neutrino 2002, Brief Conference Report:

The `XXth International Conference on Neutrino Physics and Astrophysics (Neutrino 2002)', jointly organized by the Max Planck Institute of Physics andMunich Technical University, was held at Munich, Germany, from May 24-30, 2002.The topics discussed at the conference cover essentially the entire spectrum ofneutrino physics and neutrino astrophysics, both from an experimental and atheoretical perspective.Neutrino 2002 was attended by more than 450 registered participants.Following the tradition of previous conferences in this series, the scientific program consisted of invited plenary talks, which mostly were of the review type, and a poster session.

Among the many excellent results and new ideas which were presented and extensively discussed at Neutrino 2002, quite a number are outstanding.Undoubtedly, this applies to the latest results on the neutral current measurement of solar neutrinos with the SNO detector, which not only proves neutrino oscillations between active flavours as the solution to the long-standing solar neutrino puzzle, but also validates our theoretical understanding of the processes taking place in the solar interior.The phenomenon of neutrino oscillations has independently been verified in measurements of atmospheric neutrinos and in the terrestrial K2K long baseline oscillation experiment.The overall picture emerging from a combined analysis of the results from solar, atmospheric, nuclear reactor and accelerator neutrino experiments provides an internally consistent picture in the frame of massive, oscillating neutrinos. For the first time now, it allows to pinpoint the intrinsic neutrino parameters "neutrino rest masses" and "lepton mixing angles" within a few, well defined regions in parameter space.

Particular emphasis in the discussion of next generation projects was lying on high intensity, long baseline superbeams and neutrino beams from a future neutrino factory. The physics potential of these facilities to further pinpoint the mixing angles and to determine leptonic CP properties is particularly large for neutrino parameters in the "LMA"-region of parameter space. The presented experimental results and the discussions at Neutrino 2002 showed that it is this parameter region yielding the best fit to all available data.

In view of the investigation of intrinsic neutrino parameters, Neutrino 2002 saw extensive and controversial discussions on the interpretation of a recently published claim of positive evidence for neutrinoless double beta decay, which - if correct - would prove the neutrino to be a Majorana particle.

In the field of direct neutrino mass determinations with kinematical methods, improved results were presented by the Mainz Neutrino Mass Experiment. The funded large-scale successor project KATRIN, targeting at a sub-eV sensitivity, was discussed in detail.

Neutrino astrophysics also has advanced quite a lot since the previous Neutrino Conference: There were new results from the neutrino telescopes in lake Baikal and at the south pole, as well as progress reports on the next generation projects at south pole and in the Mediterranean.

The French Edelweiss experiment searching for non-baryonic dark matter has presented its new data on Wimp-nucleus scattering for the first time. This new measurement is hardly consistent to results obtained previously with the DAMA dark matter experiment and essentially rules out the DAMA favoured parameter region.

In summary, the scientific program of Neutrino 2002 was of an exceptional quality. Stimulated by the many excellent results and new findings presented, the conference was also characterized by extremely lively discussions. The presentations and discussions underlined that neutrino physics and neutrino astrophysics are highly interesting, rapidly evolving and flourishing interdisciplinary areas of research.

Additional Information: - The transparencies of all plenary talks and electronic versions of the majority of the poster contributions are available for download from the conference web page at the address http://neutrino2002.ph.tum.de - The proceedings of Neutrino-2002 will be published as a separate volume of Nuclear Physics B (Proceedings Supplement).