Temperature Dependence of the FIR Reflectance of LaSrGaO4

The reflectance of single crystal LaSrGaO4 has been measured from approx 50 to 40000 cm^-1 along the "a" and "c" axis. The optical properties have been calculated from a Kramers-Kronig analysis of the reflectance for both polarizations. The reflectance curves have been fit using a product of Lorentzian oscillators.Comment: 12 pages including 5 figures and 2 tables. Latex file, Requires elsart.sty file and eps

Measurement of γ\gamma-ray production via neutron-16^{16}O reaction using a 77 MeV quasi-monoenergetic neutron beam

Understanding of $\gamma$-ray production via neutron interactions on oxygen is essential for the study of neutrino neutral-current quasielastic interactions in water Cherenkov detectors. A measurement of $\gamma$-ray production from such reactions was performed using a 77~MeV quasi-monoenergetic neutron beam. Several $\gamma$-ray peaks, which are expected to come from neutron-${\rm ^{16}O}$ reactions, are observed and production cross sections are measured for nine $\gamma$-ray components of energies between 2 and 8~MeV. These are the first measurements at this neutron energy using a nearly monoenergitic beam.Comment: 16 pages, 20 figures, 4 table

Improved Measurement of the K+ to pi+ nu nubar Branching Ratio

An additional event near the upper kinematic limit for K+ to pi+ nu nubar has been observed by Experiment E949 at Brookhaven National Laboratory. Combining previously reported and new data, the branching ratio is B(K+ to pi+ nu nubar)= 1.47 (+1.30, - 0.89) x 10-10 based on three events observed in the pion momentum region 211<P<229 MeV/c. At the measured central value of the branching ratio, the additional event had a signal-to-background ratio of 0.9

Further Evidence for the Decay K+ to pi+ neutrino-antineutrino

Additional evidence for the rare kaon decay K+ to pi+ neutrino-antineutrino has been found in a new data set with comparable sensitivity to the previously reported result. One new event was observed in the pion momentum region examined, 211<P<229 MeV/c, bringing the total for the combined data set to two. Including all data taken, the backgrounds were estimated to contribute 0.15 pm 0.05 events. The branching ratio is B=1.57^{+1.75}_{-0.82} 10^{-10}.Comment: 10 pages, 2 figure