Procedures and results on hardware level detector calibration in Super-Kamiokande (SK) are presented in this paper. In particular, we report improvements made in our calibration methods for the ...experimental phase IV in which new readout electronics have been operating since 2008. The topics are separated into two parts. The first part describes the determination of constants needed to interpret the digitized output of our electronics so that we can obtain physical numbers such as photon counts and their arrival times for each photomultiplier tube (PMT). In this context, we developed an in-situ procedure to determine high-voltage settings for PMTs in large detectors like SK, as well as a new method for measuring PMT quantum efficiency and gain in such a detector. The second part describes the modeling of the detector in our Monte Carlo simulation, including in particular the optical properties of its water target and their variability over time. Detailed studies on the water quality are also presented. As a result of this work, we achieved a precision sufficient for physics analysis over a wide energy range (from a few MeV to above a TeV). For example, the charge determination was understood at the 1% level, and the timing resolution was 2.1 nsec at the one-photoelectron charge level and 0.5 nsec at the 100-photoelectron charge level.
Phys. Rev. Lett. 112, 091805 (2014) We report an indication that the elastic scattering rate of solar $^8$B
neutrinos with electrons in the Super-Kamiokande detector is larger when the
neutrinos pass ...through the Earth during nighttime. We determine the day/night
asymmetry, defined as the difference of the average day rate and average night
rate divided by the average of those two rates, to be
$(-3.2\pm1.1(\text{stat})\pm0.5(\text{syst}))\%$, which deviates from zero by
2.7 $\sigma$. Since the elastic scattering process is mostly sensitive to
electron-flavored solar neutrinos, a non-zero day/night asymmetry implies that
the flavor oscillations of solar neutrinos are affected by the presence of
matter within the neutrinos' flight path. Super-Kamiokande's day/night
asymmetry is consistent with neutrino oscillations for
$4\times10^{-5}$eV$^2\leq\Delta m^2_{21}\leq7\times10^{-5}$eV$^2$ and large
mixing values of $\theta_{12}$, at the $68\%$ C.L.
A spatial variation in the two-dimensional crystal lattice orientation of L-DPPC monolayer on a hydrophobic substrate was observed by use of an electron microscope with diffraction and dark-field ...techniques. It is shown that the monolayer has a mosaic structure with domains, each of which consists of a region with a homogeneously oriented lattice of L-DPPC molecules. The domain structure of L-DPPC monolayer on a hydrophilic surface is also discussed.
A new measurement of the ital Ksub ital Lr arrowital esup +ital esup minusgammagamma branching ratio was carried out in Fermilab experiment E799. We observed 58 ital Ksub ital Lr arrowital esup +ital ...esup minusgammagamma events. The measured branching ratio is ital B(ital Ksub ital Lr arrowital esup +ital esup minusgammagamma, ital Esub gammasup *gt5 MeV) = 6.5plus minus1.2 (stat) plus minus0.6 (syst) times10sup minus7.
Full text
Available for:
CMK, CTK, FMFMET, IJS, NUK, PNG, UM
The combined cross section for absorption and charge exchange interactions of positively charged pions with carbon nuclei for the momentum range 200 MeV/c to 300 MeV/c have been measured with the ...DUET experiment at TRIUMF. The uncertainty is reduced by nearly half compared to previous experiments. This result will be a valuable input to existing models to constrain pion interactions with nuclei.
In previous papers, the synthesis of liquid-crystalline polyurethanes containing mesomorphic moieties in the main chain and in side chains was reported. Liquid crystalline polymers with side groups ...containing the cholesterol moiety have also been studied. The main focus of attention has centered around the study of phase transitions of acrylic and methacrylic derivatives of cholesterol. The synthesis of a new type of liquid-crystalline polyurethane containing the cholesterol moiety in side chains is described. 6 ref.--AA
We report on a search for the decay ital Ksub ital Lr arrowpisup 0nubar nu by the Fermilab E799 Collaboration. The partial width for this mode is related in a calculable way to the ital CP violation ...parameters of the standard model. In particular, the decay ital Ksub ital Lr arrowpisup 0nubar nu is predicted to proceed almost entirely via a direct ital CP violating amplitude. No events were observed, allowing us to set an upper limit on the branching ratio of ital B(ital Ksub ital Lr arrowpisup 0nubar nu)lt5.8times10sup minus5 at the 90% confidence level.
Full text
Available for:
CMK, CTK, FMFMET, IJS, NUK, PNG, UM
Comparing the predicted amino acid sequence between two Japanese potato virus Y (PVY) strains, necrotic strain and ordinary strain, it was found that the C-terminal regions ...(H2N-HTTEDVSPSMHTLLGVKNM-COOH) of the coat proteins in the two strains were completely conserved. The conserved amino acid sequence was also found in the C-terminal region coat protein of PVY-36, a strain which did not react with monoclonal antibodies specific to the necrotic and the ordinary strain respectively. Antibodies were produced against a synthetic polypeptide PVY-C19 consisting of 19 amino acids, which correspond to the C-terminal region of the coat protein, using 4 coupling combinations of polypeptide PVY-C19 to protein carriers. Carrier-free polypeptides and those coupled to ovalbumin with ECDI (ethyl-dimethylaminopropyl carbodiimide) produced high titer of antibodies and detected PVY strains from PVY-infected plants by Western blot analysis and by ELISA.
We measured the coefficient of roughness in a hydraulic experiment using a concrete channel whose surface was treated to simulate abraded concrete. Various surface roughness parameters were trialed ...to determine those that best represent the surface roughness of the experimental concrete panels. The calculated coefficient of roughness (n) was 0.013. This value is within the range of the design standards for concrete channels. The height distribution of the surface of the experimental channel was characterized by skewness that showed bias of the height distribution of the roughness. The equivalent roughness of the simulated abraded concrete channel can be expressed as ks = 2 × Ra for Ra of 0.5 ± 0.12 mm or ks = 0.26 × Rz for Rz of 4 ± 1.43 mm.
Phys. Rev. Lett. 113, 121802 (2014) We present the results of searches for nucleon decay via bound neutron to
antineutrino plus pizero and proton to antineutrino plus piplus using data from
a ...combined 172.8 kiloton-years exposure of Super-Kamiokande-I, -II, and -III.
We set lower limits on the partial lifetime for each of these modes. For
antineutrino pizero, the partial lifetime is >1.1x10^{33} years; for
antineutrino piplus, the partial lifetime is >3.9x10^{32} years at 90%
confidence level.
