7,838 research outputs found
Low-energy three-body charge transfer reactions with Coulomb interaction in the final state
Three-body charge transfer reactions with Coulomb interaction in the final
state are considered in the framework of coordinate-space integro-differential
Faddeev-Hahn-type equations within two- and six-state close coupling
approximations. The method is employed to study direct muon transfer in
low-energy collisions of the muonic hydrogen H by helium (He) and
lithium (Li) nuclei. The experimentally observed isotopic dependence is
reproduced.Comment: 14 pages REVTeX, accepted for publication in Journal of Physics
CMS endcap RPC gas gap production for upgrade
The CMS experiment will install a RE4 layer of 144 new Resistive Plate Chambers (RPCs) on the existing york YE3 at both endcap regions to trigger high momentum muons from the proton-proton interaction. In this paper, we present the detailed procedures used in the production of new RPC gas gaps adopted in the CMS upgrade. Quality assurance is enforced as ways to maintain the same quality of RPC gas gaps as the existing 432 endcap RPC chambers that have been operational since the beginning of the LHC operation
Low-energy quenching of positronium by helium
Very low-energy scattering of orthopositronium by helium has been
investigated for simultaneous study of elastic cross section and pick-off
quenching rate using a model exchange potential. The present calculational
scheme, while agrees with the measured cross section of Skalsey et al,
reproduces successfully the parameter ^ 1Z_{\makebox{eff}}, the effective
number of electrons per atom in a singlet state relative to the positron.
Together with the fact that this model potential also leads to an agreement
with measured medium energy cross sections of this system, this study seems to
resolve the long-standing discrepancy at low energies among different
theoretical calculations and experimental measurements.Comment: 4 latex pages, 3 postscript figure
A Carbon Corrosion Model to Evaluate the Effect of Steady State and Transient Operation of a Polymer Electrolyte Membrane Fuel Cell
A carbon corrosion model is developed based on the formation of surface
oxides on carbon and platinum of the polymer electrolyte membrane fuel cell
electrode. The model predicts the rate of carbon corrosion under potential hold
and potential cycling conditions. The model includes the interaction of carbon
surface oxides with transient species like OH radicals to explain observed
carbon corrosion trends under normal PEM fuel cell operating conditions. The
model prediction agrees qualitatively with the experimental data supporting the
hypothesis that the interplay of surface oxide formation on carbon and platinum
is the primary driver of carbon corrosion
Performance of the Gas Gain Monitoring system of the CMS RPC muon detector and effective working point fine tuning
The Gas Gain Monitoring (GGM) system of the Resistive Plate Chamber (RPC)
muon detector in the Compact Muon Solenoid (CMS) experiment provides fast and
accurate determination of the stability in the working point conditions due to
gas mixture changes in the closed loop recirculation system. In 2011 the GGM
began to operate using a feedback algorithm to control the applied voltage, in
order to keep the GGM response insensitive to environmental temperature and
atmospheric pressure variations. Recent results are presented on the feedback
method used and on alternative algorithms
Economic and health burden of brucellosis in Kazakhstan
Brucellosis is a widespread zoonotic disease considered as an emerging and re-emerging disease with a resulting threat of public health and animal health. Official reports document an animal incidence in Kazakhstan of about 0.6% per year, and the country still registers high number of human cases annually . The main objective of this paper was to evaluate the distribution and economic impact of brucellosis in Kazakhstan. We analysed human disease incidence data obtained from the Government Sanitary & Epidemiological Service with the aim to estimate the burden of disease in terms of disability-adjusted life years (DALYs). We also estimated the economic impact in terms of monetary losses. Additionally, we mapped the geographical distribution of the disease throughout Kazakhstan. In total, 1,334 human cases of brucellosis were registered in 2015 in Kazakhstan that resulted in 713 DALYs. Around US Dollar 21 million was spent on compensation for animals that had to be slaughtered due to brucellosis, and an additional US Dollar 24 million was spent on testing animals. Animal brucellosis and human brucellosis occur throughout the whole country, some trends of which are reviewed in this paper. We estimated the burden of the disease and explored possible explanation for high human incidence rates. This paper is the first to estimate the human burden of disease and the economic costs in Kazakhstan. Both of these are substantial
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