4,147 research outputs found
Effects of different field expansions on omnidirectional proton counting rate data
Field expansion effects on omnidirectional proton counting rate dat
Plasma clouds in the magnetosphere
Injection of hot plasma clouds into magnetosphere during magnetospheric substorm
A Spherical Plasma Dynamo Experiment
We propose a plasma experiment to be used to investigate fundamental
properties of astrophysical dynamos. The highly conducting, fast-flowing plasma
will allow experimenters to explore systems with magnetic Reynolds numbers an
order of magnitude larger than those accessible with liquid-metal experiments.
The plasma is confined using a ring-cusp strategy and subject to a toroidal
differentially rotating outer boundary condition. As proof of principle, we
present magnetohydrodynamic simulations of the proposed experiment. When a von
K\'arm\'an-type boundary condition is specified, and the magnetic Reynolds
number is large enough, dynamo action is observed. At different values of the
magnetic Prandtl and Reynolds numbers the simulations demonstrate either
laminar or turbulent dynamo action
Quark-hadron duality in neutrino scattering
We present a phenomenological model of the quark-hadron transition in
neutrino-nucleon scattering. Using recently extracted weak nucleon transition
form factors, we investigate the extent to which local and global quark-hadron
duality is applicable in the neutrino F_1, F_2 and F_3 structure functions, and
contrast this with duality in electron scattering. Our findings suggest that
duality works relatively well for neutrino-nucleon scattering for the F_2 and
F_3 structure functions, but not as well for F_1. We also calculate the
quasielastic, resonance and deep inelastic contributions to the Adler sum rule,
and find it to be satisfied to within 10% for 0.5 < Q^2 < 2 GeV^2.Comment: 28 pages, 6 figure
Time integration in the code Zgoubi and external usage of PTC's structures
The purpose of this note is to describe Zgoubi's integrator and to describe some pitfals for time based integration when used in accelerators. We show why the convergence rate of an integrator can be affected by an improper treatment at the boundary when time is used as the integration variable. We also point out how the code PTC can be used as a container by other tracking engine. This work is not completed as far as incorporation of Zgoubi is concerned
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