2,283 research outputs found
Neutrino Oscillations at Reactors: What Next?
We shortly review past and future experiments at reactors aimed at searches
for neutrino masses and mixing. We also consider new idea to search at
Krasnoyarsk for small mixing angle oscillations in the atmosheric neutrino mass
parameter region.Comment: 9 pages, LaTeX 2.09, 6 Postscript figures. Talk given at
Non-Accelerator New Physics Conference, Dubna, 28.06-03.07.199
Resonant X-Ray Scattering Measurements of a Spatial Modulation of the Cu 3d and O 2p Energies in Stripe-Ordered Cuprate Superconductors
A prevailing description of the stripe phase in underdoped cuprate
superconductors is that the charge carriers (holes) phase segregate on a
microscopic scale into hole rich and hole poor regions. We report resonant
elastic x-ray scattering measurements of stripe-ordered
LaNdSrCuO at the Cu and O absorption
edges that identify an additional feature of stripe order. Analysis of the
energy dependence of the scattering intensity reveals that the dominant
signature of the stripe order is a spatial modulation in the energies of Cu 3d
and O 2p states rather than the large modulation of the charge density
(valence) envisioned in the common stripe paradigm. These energy shifts are
interpreted as a spatial modulation of the electronic structure and may point
to a valence-bond-solid interpretation of the stripe phase.Comment: 5 pages, 2 figure
Automated Failure Detection in Computer Vision Systems
Human validation of computer vision systems increase their operatingcosts and limits their scale. Automated failure detection canmitigate these constraints and is thus of great importance to thecomputer vision industry. Here, we apply a deep neural networkto detect computer vision failures on vehicle detection tasks. Theproposed model is a convolution neural network that estimates theoutput quality of a vehicle detector. We train the network to learnto estimate a pixel-level F1 score between the vehicle detector andhuman annotated data. The model generalizes well to testing data,providing a mechanism for identifying detection failures
The Kr2Det project: Search for mass-3 state contribution |U_{e3}|^2 to the electron neutrino using a one reactor - two detector oscillation experiment at Krasnoyarsk underground site
The main physical goal of the project is to search with reactor antineutrinos
for small mixing angle oscillations in the atmospheric mass parameter region
around {\Delta}m^{2}_{atm} ~ 2.5 10^{-3} eV^2 in order to find the element
U_{e3} of the neutrino mixing matrix or to set a new more stringent constraint
(U_{e3} is the contribution of mass-3 state to the electron neutrino flavor
state). To achieve this we propose a "one reactor - two detector" experiment:
two identical antineutrino spectrometers with 50 ton liquid scintillator
targets located at ~100 m and ~1000 m from the Krasnoyarsk underground reactor
(~600 mwe). In no-oscillation case ratio of measured positron spectra of the
\bar{{\nu}_e} + p \to e^{+} + n reaction is energy independent. Deviation from
a constant value of this ratio is the oscillation signature. In this scheme
results do not depend on the exact knowledge of the reactor power, nu_e
spectra, burn up effects, target volumes and, which is important, the
backgrounds can periodically be measured during reactor OFF periods. In this
letter we present the Krasnoyarsk reactor site, give a schematic description of
the detectors, calculate the neutrino detection rates and estimate the
backgrounds. We also outline the detector monitoring and calibration
procedures, which are of a key importance. We hope that systematic
uncertainties will not accede 0.5% and the sensitivity U^{2}_{e3} ~4 10^{-3}
(at {\Delta}m^{2} = 2.5 10^{-3} eV^2) can be achieved.Comment: Latex 2e, 9 pages and 5 ps figure
The symmetry of charge order in cuprates
Charge-ordered ground states permeate the phenomenology of 3d-based
transition metal oxides, and more generally represent a distinctive hallmark of
strongly-correlated states of matter. The recent discovery of charge order in
various cuprate families fueled new interest into the role played by this
incipient broken symmetry within the complex phase diagram of high-Tc
superconductors. Here we use resonant X-ray scattering to resolve the main
characteristics of the charge-modulated state in two cuprate families: Bi2201
and YBCO. We detect no signatures of spatial modulations along the nodal
direction in Bi2201, thus clarifying the inter-unit-cell momentum-structure of
charge order. We also resolve the intra-unit-cell symmetry of the charge
ordered state, which is revealed to be best represented by a bond-order with
modulated charges on the O-2p orbitals and a prominent d-wave character. These
results provide insights on the microscopic description of charge order in
cuprates, and on its origin and interplay with superconductivity.Comment: A high-resolution version with supplementary material can be found
at:
http://www.phas.ubc.ca/~quantmat/ARPES/PUBLICATIONS/Articles/CDW_symmetry.pd
Bortezomib in Kidney Transplantation
Although current therapies for pretransplant desensitization and treatment of antibody-mediated rejection (AMR) have had some success, they do not specifically deplete plasma cells that produce antihuman leukocyte antigen (HLA) antibodies. Bortezomib, a proteasome inhibitor approved for the treatment of multiple myeloma (a plasma cell neoplasm), induces plasma cell apoptosis. In this paper we review the current body of literature regarding the use of this biological agent in the field of transplantation. Although limited experience with bortezomib may seem to show promise in the realm of transplant recipients desensitization and treatment of AMR, there is also experience that may suggest otherwise. Bortezomib's role in desensitization protocols and treatment of AMR will be defined better as more clinical data and trials become available
Inverse Beta Decay in a Nonequilibrium Antineutrino Flux from a Nuclear Reactor
The evolution of the reactor antineutrino spectrum toward equilibrium above
the inverse beta-decay threshold during the reactor operating period and the
decay of residual antineutrino radiation after reactor shutdown are considered.
It is found that, under certain conditions, these processes can play a
significant role in experiments seeking neutrino oscillations.Comment: 8 pages including 5 ps figure
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