arXiv subjects
Publications and source records attributed to Patrick Huber.
We discuss the potential of long-baseline neutrino oscillation experiments to determine deviations from maximal ν_μ-ν_τmixing. We compare the obtainable sensitivities to predictions from neutrino mass models and to the size of quantum corrections. We find that the theoretical expectations for deviations are typically well within experimental reach.
We present an X-ray diffraction study of the normale alkane nonadecane C_{19}H_{40} embedded in nanoporous Vycor glass. The confined molecular crystal accomplishes a close-packed structure by alignment of the rod-like molecules parallel to the pore axis while sacrificing one basic principle known from the bulk state, i.e. the lamellar ordering of the molecules. Despite this disorder, the phase transitions observed in the confined solid mimic the phase behavior of the 3D unconfined crystal, though enriched by the appearance of a true rotator phase known only from longer alkane chains.
We show that for a neutrino factory baseline of $L \sim 7300 km - 7 600 km$ a ``clean'' measurement of $\sin^2 2 θ_{13}$ becomes possible, which is almost unaffected by parameter degeneracies. We call this baseline "magic" baseline, because its length only depends on the matter density profile. For a complete analysis, we demonstrate that the combination of the magic baseline with a baseline of 3000 km is the ideal solution to perform equally well for the $\sin^2 2 θ_{13}$, sign of $Δm_{31}^2$, and CP violation sensitivities. Especially, this combination can very successfully resolve parameter degeneracies even below $\sin^2 2 θ_{13} < 10^{-4}$.
I give a short overview about the possibilities and problems related to the measurement of CP violation in long baseline experiments. Special attention is paid to the issue of degeneracies and a method for their resolution is quantitatively discussed. The CP violation reach for different experiments is compared in dependence of $\sin^22θ_{13}$ and $\dm{21}$. Furthermore a short comment about the possible effects of matter induced T violation is made. Finally the limits on CPT violation obtainable at a neutrino factory are shown.
We compare the physics potential of planned superbeams with the one of neutrino factories. Therefore, the experimental setups as well as the most relevant uncertainties and errors are considered on the same footing as much as possible. We use an improved analysis including the full parameter correlations, as well as statistical, systematical, and degeneracy errors. Especially, degeneracies have so far not been taken into account in a numerical analysis. We furthermore include external input, such as improved knowledge of the solar oscillation parameters from the KamLAND experiment. This allows us to determine the limiting uncertainties in all cases. For a specific comparison, we choose two representatives of each class: For the superbeam, we take the first conceivable setup, namely the JHF to SuperKamiokande experiment, as well as, on a longer time scale, the JHF to HyperKamiokande experiment. For the neutrino factory, we choose an initially conceivable setup and an advanced machine. We determine the potential to measure the small mixing angle sin^2 2 theta_{13}, the sign of Delta m^2_{31}, and the leptonic CP phase $\deltacp$, which also implies that we compare the limitations of the different setups. We find interesting results, such as the complete loss of the sensitivity to the sign of Delta m^2_{31} due to degeneracies in many cases.
A continuous surface wetting transition, pinned to a solid/liquid/liquid/vapor tetra coexistence point, is studied by x-ray reflectivity in liquid Ga-Bi binary alloys. The short-range surface potential is determined from the measured temperature evolution of the wetting film. The thermal fluctuations are shown to be insufficient to induce a noticeable breakdown of mean-field behavior, expected in short-range-interacting systems due to their $d_u=3$ upper critical dimensionality.