253 research outputs found
Plasmon assisted synthesis of highly fluorescing silver quantum cluster / polymer composites for biochemical sensing
Validation of a fully autonomous phosphate analyser based on a microfluidic lab-on-a-chip
This work describes the design of a phosphate analyser that utilises a microfluidic lab-on-a-chip. The analyser contains all the required chemical storage, pumping and electronic components to carry out a complete phosphate assay. The system is self-calibrating and self-cleaning, thus capable of long-term operation. This was proven by a bench top calibration of the analyser using standard solutions and also by comparing the analyser's performance to a commercially available phosphate monitor installed at a waste water treatment plant. The output of the microfluidic lab-on-a-chip analyser was shown to have sensitivity and linear range equivalent to the commercially available monitor and also the ability to operate over an extended period of time
Measurement of and charged current inclusive cross sections and their ratio with the T2K off-axis near detector
We report a measurement of cross section and the first measurements of the cross section
and their ratio
at (anti-)neutrino energies below 1.5
GeV. We determine the single momentum bin cross section measurements, averaged
over the T2K -flux, for the detector target material (mainly
Carbon, Oxygen, Hydrogen and Copper) with phase space restricted laboratory
frame kinematics of 500 MeV/c. The
results are and $\sigma(\nu)=\left( 2.41\
\pm0.022{\rm{(stat.)}}\pm0.231{\rm (syst.)}\ \right)\times10^{-39}^{2}R\left(\frac{\sigma(\bar{\nu})}{\sigma(\nu)}\right)=
0.373\pm0.012{\rm (stat.)}\pm0.015{\rm (syst.)}$.Comment: 18 pages, 8 figure
Searches for baryon number violation in neutrino experiments: a white paper
Baryon number conservation is not guaranteed by any fundamental symmetry within the standard model, and therefore has been a subject of experimental and theoretical scrutiny for decades. So far, no evidence for baryon number violation has been observed. Large underground detectors have long been used for both neutrino detection and searches for baryon number violating processes. The next generation of large neutrino detectors will seek to improve upon the limits set by past and current experiments and will cover a range of lifetimes predicted by several Grand Unified Theories. In this White Paper, we summarize theoretical motivations and experimental aspects of searches for baryon number violation in neutrino experiments
Search for Lorentz and CPT violation using sidereal time dependence of neutrino flavor transitions over a short baseline
A class of extensions of the Standard Model allows Lorentz and CPT violations, which can be identified
by the observation of sidereal modulations in the neutrino interaction rate. A search for such modulations
was performed using the T2K on-axis near detector. Two complementary methods were used in this study,
both of which resulted in no evidence of a signal. Limits on associated Lorentz and CPT-violating terms
from the Standard Model extension have been derived by taking into account their correlations in this
model for the first time. These results imply such symmetry violations are suppressed by a factor of more
than 10 20 at the GeV scale
Determination of the Form Factors for the Decay B0 --> D*-l+nu_l and of the CKM Matrix Element |Vcb|
We present a combined measurement of the Cabibbo-Kobayashi-Maskawa matrix element and of the parameters , , and , which fully characterize the form factors of the decay in the framework of HQET, based on a sample of about 52,800 decays recorded by the BABAR detector. The kinematical information of the fully reconstructed decay is used to extract the following values for the parameters (where the first errors are statistical and the second systematic): , , , . By combining these measurements with the previous BABAR measurements of the form factors which employs a different technique on a partial sample of the data, we improve the statistical accuracy of the measurement, obtaining: and Using the lattice calculations for the axial form factor , we extract , where the third error is due to the uncertainty in
EuFeAs under high pressure: an antiferromagnetic bulk superconductor
We report the ac magnetic susceptibility and resistivity
measurements of EuFeAs under high pressure . By observing nearly
100% superconducting shielding and zero resistivity at = 28 kbar, we
establish that -induced superconductivity occurs at ~30 K in
EuFeAs. shows an anomalous nearly linear temperature dependence
from room temperature down to at the same . indicates that
an antiferromagnetic order of Eu moments with ~20 K persists
in the superconducting phase. The temperature dependence of the upper critical
field is also determined.Comment: To appear in J. Phys. Soc. Jpn., Vol. 78 No.
Study of the Exclusive Initial-State Radiation Production of the System
A study of exclusive production of the system through initial-state r adiation is performed in a search for charmonium states, where or . The mesons are reconstructed in the , , and decay modes. The is reconstructed through the decay mode. The analysis makes use of an integrated luminosity of 288.5 fb collected by the BaBar experiment. The mass spectrum shows a clear signal. Further structures appear in the 3.9 and 4.1 GeV/ regions. No evidence is found for Y(4260) decays to , implying an up per limit \frac{\BR(Y(4260)\to D \bar D)}{\BR(Y(4260)\to J/\psi \pi^+ \pi^-)} < 7.6 (95 % confidence level)
A search for the decay
We search for the rare flavor-changing neutral-current decay in a data sample of 82 fb collected with the {\sl BABAR}
detector at the PEP-II B-factory. Signal events are selected by examining the
properties of the system recoiling against either a reconstructed hadronic or
semileptonic charged-B decay. Using these two independent samples we obtain a
combined limit of
at the 90% confidence level. In addition, by selecting for pions rather than
kaons, we obtain a limit of using only the hadronic B reconstruction method.Comment: 7 pages, 8 postscript figures, submitted to Phys. Rev. Let
- …