We report the first observation of a charm-strange meson D(+)(sJ)(2632) at a mass of 2632.5+/-1.7 MeV/c(2) in data from SELEX, the charm hadro-production experiment E781 at Fermilab. This state is ...seen in two decay modes, D(+)(s)eta and D0K+. In the D(+)(s)eta decay mode we observe a peak with 101 events over a combinatoric background of 54.9 events at a mass of 2635.4+/-3.3 MeV/c(2). There is a corresponding peak of 21 events over a background of 6.9 at 2631.5+/-2.0 MeV/c(2) in the decay mode D0K+. The decay width of this state is <17 MeV/c(2) at 90% confidence level. The relative branching ratio Gamma(D0K+)/Gamma(D(+)(s)eta) is 0.14+/-0.06. The mechanism that keeps this state narrow is unclear. Its decay pattern is also unusual, being dominated by the D(+)(s)eta decay mode.
We consider an alternative explanation for the deficit of nu_e in Ga solar neutrino calibration experiments and of the anti nu_e in short baseline reactor experiments by a model where neutrinos can ...oscillate into sterile Kaluza-Klein modes that can propagate in compactified sub-micrometer flat extra dimensions. We have analyzed the results of the Gallium radioactive source experiments and 19 reactor experiments with baseline shorter than 100 m, and showed that these data can be fitted into this scenario. The values of the lightest neutrino mass and of the size of the largest extra dimension that are compatible with these experiments are mostly not excluded by other neutrino oscillation experiments.
Phys.Rev.Lett.95:081801,2005 The Xi^0 muon semi-leptonic decay has been observed for the first time with
nine identified events using the KTeV beam line and detector at Fermilab. The
decay is ...normalized to the Xi^0 beta decay mode and yields a value for the
ratio of decay rates of $(1.8^{+0.7}_{-0.5}(stat.)\pm0.2(syst.))\times
10^{-2}$. This is in agreement with the SU(3) flavor symmetric quark model.
We consider a model where right-handed neutrinos propagate in a large compactified extra dimension, engendering Kaluza-Klein (KK) modes, while the standard model particles are restricted to the usual ...4-dimensional brane. A mass term mixes the KK modes with the standard left-handed neutrinos, opening the possibility of change the 3 generation mixing pattern. We derive bounds on the maximum size of the extra dimension from neutrino oscillation experiments. We show that this model provides a possible explanation for the deficit of nu_e in Ga solar neutrino calibration experiments and of the anti-nu_e in short baseline reactor experiments.
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