4,565 research outputs found
Test of charge conjugation invariance in the decay of the eta meson into pi(+)pi(-)pi(0)
In this work we present the preliminary results of the analysis of the pp->pp
eta(->pp pi(+)pi(-)pi(0) reaction aiming to test the charge conjugation
symmetry C in strong interactions. Based on approximately identified
eta->pi(+)pi(-)pi(0) decay events we have extracted asymmetry parameters
sensitive to C symmetry violation for different isospin values of the final
state and we have established that all are consistent with zero within the
obtained accuracy.Comment: MESON2012 - 12th International Workshop on Meson Production,
Properties and Interactio
Study of the eta meson production with polarized proton beam
The pp-> pp eta reaction was investigated at excess energies of 15 MeV and 72
MeV using the azimuthally symmetric WASA detector and a polarized proton beam
of the Cooler Synchrotron COSY. The aim of the studies is the determination of
partial wave contributions to the production process of the eta meson in
nucleon-nucleon collisions. Here we present preliminary results of the
extraction of the position of the interaction region with respect to the WASA
detector and preliminary results on the degree of polarization of the COSY
proton beam used in the experiment.Comment: Invited talk at the Second International Symposium on Mesic Nuclei,
Cracow, Poland, September 22-25 201
Characteristics of modern atmospheric dust deposition in snow on the Penny Ice Cap, Baffin Island, Arctic Canada
We evaluated the concentration, size and distribution of insoluble dust microparticles in snowpits on the Penny Ice Cap (PIC), Baffin Island, to define (1) the characteristics of modern atmospheric dust deposition at the site, (2) the relative contributions of proximal and distal dust sources, and (3) the effects of summer melting on depositional signals in snow. The mean concentration (143 mg kg−1), flux (4.8 mg cm2 yr−1) and diameter (2.3 mm) of dust deposited on the PIC are similar to those observed in remote Arctic sites such as central Greenland, implying that dust is primarily supplied through long-range transport from far-removed source regions (at least 102–103 km distant). There is evidence for two seasonal maxima of dust deposition, one in late winter-early spring and one in late summer-early fall, although seasonal signals can not always be resolved in the snowpack due to some post-depositional particle migration with summer melt. However, ice layers appear to limit the mobility of particles, thereby preserving valuable paleoclimatic information in the PIC ice core dust record at a multi-annual to decadal temporal resolution
Long-Term Effects of Neutron Absorber and Fuel Matrix Corrosion on Criticality
Proposed waste package designs will require the addition of neutron absorbing material to prevent the possibility of a sustained chain reaction occurring in the fuel in the event of water intrusion. Due to the low corrosion rates of the fuel matrix and the Zircaloy cladding, there is a possibility that the neutron absorbing material will corrode and leak from the waste container long before the subsequent release of fuel matrix material. An analysis of the release of fuel matrix and neutron absorber material based on a probabilistic model was conducted and the results were used to prepare input to KENO-V, an neutron criticality code. The results demonstrate that, in the presence of water, the computed values of k{sub eff} exceeded the maximum of 0.95 for an extended period of time
The Value of Information in Reservoir Management
This paper analyzes in quantitative terms the effectiveness of information in real-time operation of multipurpose reservoirs. For this, a simple and heuristic method strongly based on the experience of the manager is proposed and tested on the case of Lake Como (northern Italy). Particular attention is devoted to the possibility of evaluating the surplus of benefit due to the information available in real-time in addition to reservoir storage (e.g., snow cover, aquifer depth, and rainfall in the catchment). Moreover, a management scheme based on the direct use of the raw data is compared with a more sophisticated scheme using inflow predictors. Surprisingly, the first scheme, although more simple, performs better, thus justifying to a certain extent the little interest that practitioners sometimes seem to have for real-time forecasting techniques
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