3,463 research outputs found
KEK effort for high field magnets
KEK has emphasized efforts to develop the RHQNb3Al superconductor and a
sub-scale magnet reaching 13 T towards the HL-LHC upgrade in last years. In
addition, relevant R&D regarding radiation resistance has been carried out. For
higher field magnets beyond 15 T, HTS in combination with A15 superconductors
should be one of baseline materials. However, all these superconductors are
very sensitive to stress and strain and thorough understanding of behaviour is
truly desired for realization of high field magnets. KEK has launched a new
research subject on stress/strain sensitivity of HTS and A15 superconductors in
collaboration with the neutron diffraction facility at J-PARC and High Field
Laboratory in Tohoku University. Present activity for high field magnets at KEK
is reported.Comment: 4 pages, contribution to the EuCARD-AccNet-EuroLumi Workshop: The
High-Energy Large Hadron Collider, Malta, 14 -- 16 Oct 2010; CERN Yellow
Report CERN-2011-003, pp. 41-4
Single-Particle Spin-Orbit Strengths of the Nucleon and Hyperons by SU6 Quark-Model
The quark-model hyperon-nucleon interaction suggests an important
antisymmetric spin-orbit component. It is generated from a color analogue of
the Fermi-Breit interaction dominating in the one-gluon exchange process
between quarks. We discuss the strength S_B of the single-particle spin-orbit
potential, following the Scheerbaum's prescription. Using the SU6 quark-model
baryon-baryon interaction which was recently developed by the Kyoto-Niigata
group, we calculate NN, Lambda N and Sigma N G-matrices in symmetric nuclear
matter and apply them to estimate the strength S_B. The ratio of S_B to the
nucleon strength S_N =~ -40 MeV*fm^5 is (S_Lambda)/(S_N) =~ 1/5 and
(S_Sigma)/(S_N) =~ 1/2 in the Born approximation. The G-matrix calculation of
the model FSS modifies S_Lambda to (S_Lambda)/(S_N) =~ 1/12. For S_N and
S_Sigma, the effect of the short-range correlation is comparatively weak
against meson-exchange potentials with a short-range repulsive core. The
significant reduction of the Lambda single-particle potential arises from the
combined effect of the antisymmetric LS force, the flavor-symmetry breaking
originating from the strange to up-down quark-mass difference, as well as the
effect of the short-range correlation. The density dependence of S_B is also
examined.Comment: 26 page
Final Report: The Markets and Marketing Issues of the Kona Coffee Industry
This publication looks some of the problems with markets and marketing of Kona coffee and provides some recommendations for improvement
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