4 research outputs found
Astrophysical turbulence modeling
The role of turbulence in various astrophysical settings is reviewed. Among
the differences to laboratory and atmospheric turbulence we highlight the
ubiquitous presence of magnetic fields that are generally produced and
maintained by dynamo action. The extreme temperature and density contrasts and
stratifications are emphasized in connection with turbulence in the
interstellar medium and in stars with outer convection zones, respectively. In
many cases turbulence plays an essential role in facilitating enhanced
transport of mass, momentum, energy, and magnetic fields in terms of the
corresponding coarse-grained mean fields. Those transport properties are
usually strongly modified by anisotropies and often completely new effects
emerge in such a description that have no correspondence in terms of the
original (non coarse-grained) fields.Comment: 88 pages, 26 figures, published in Reports on Progress in Physic
Physics with e+ e- linear colliders
We describe the physics potential of linear colliders in this
report. These machines are planned to operate in the first phase at a center-of
--mass energy of 500 GeV, before being scaled up to about 1 TeV. In the second
phase of the operation, a final energy of about 2 TeV is expected. The machines
will allow us to perform precision tests of the heavy particles in the Standard
Model, the top quark and the electroweak bosons. They are ideal facilities for
exploring the properties of Higgs particles, in particular in the intermediate
mass range. New vector bosons and novel matter particles in extended gauge
theories can be searched for and studied thoroughly. The machines provide
unique opportunities for the discovery of particles in supersymmetric
extensions of the Standard Model, the spectrum of Higgs particles, the
supersymmetric partners of the electroweak gauge and Higgs bosons, and of the
matter particles. High precision analyses of their properties and interactions
will allow for extrapolations to energy scales close to the Planck scale where
gravity becomes significant. In alternative scenarios, like compositeness
models, novel matter particles and interactions can be discovered and
investigated in the energy range above the existing colliders up to the TeV
scale. Whatever scenario is realized in Nature, the discovery potential of
linear colliders and the high-precision with which the properties of
particles and their interactions can be analysed, define an exciting physics
programme complementary to hadron machines.Comment: 103 pages, Late