4,663 research outputs found
Breaking Electroweak Symmetry Strongly
The problem of electroweak symmetry breaking is reviewed with discussion of
future relevant experimentation at LHC and linear colliders. The
possibility of strong electroweak symmetry breaking is examined in more detail,
using the BESS (Breaking Electroweak Symmetry Strongly) model as a basis for
the discussion. The formal constructions are briefly presented and the possible
expectations at future colliders are summarized.Comment: 20 pages, LaTeX, UGVA-DPT 1994/04-846. To appear in the Memorial
Volume for Professor Robert Marshak, edited by E.C.G. Sudarshan, World
Scientific Publishing Compan
Turbulent Contributions to Ohm's Law in Axisymmetric Magnetized Plasmas
The effect of magnetic turbulence in shaping the current density in
axisymmetric magnetized plasma is analyzed using a turbulent extension of Ohm's
law derived from the self-consistent action-angle transport theory. Besides the
well-known hyper-resistive (helicity-conserving) contribution, the generalized
Ohm's law contains an anomalous resistivity term, and a turbulent
bootstrap-like term proportional to the current density derivative. The
numerical solution of the equation for equilibrium and turbulence profiles
characteristic of conventional and advanced scenarios shows that, trough
"turbulent bootstrap" effect and anomalous resistivity turbulence can generate
power and parallel current which are a sizable portion (about 20-25%) of the
corresponding effects associated with the neoclassical bootstrap effect. The
degree of alignment of the turbulence peak and the pressure gradient plays an
important role in defining the steady-state regime. In fully bootstrapped
tokamak, the hyper-resistivity is essential in overcoming the intrinsic
limitation of the hollow current profile.Comment: 19 pages, 6 figures, journal pape
Thermodynamics of the Massive Gross-Neveu Model
We study the thermodynamics of massive Gross-Neveu models with explicitly
broken discrete or continuous chiral symmetries for finite temperature and
fermion densities. The large limit is discussed bearing attention to the
no-go theorems for symmetry breaking in two dimensions which apply to the
massless cases. The main purpose of the study is to serve as analytical
orientation for the more complex problem of chiral transition in
dimensional QCD with quarks. For any non-vanishing fermion mass we find, at
finite densities, lines of first order phase transitions. For small mass values
traces of would-be second order transitions and a tricritical point are
recognizable. We study the thermodynamics of these models, and in the model
with broken continuous chiral symmetry we examine the properties of the pion
like state.Comment: 34 pages (+18 figures, available upon request to [email protected]),
LATEX file, uses art12a.sty, macro included, UGVA-DPT 1994/06-85
Structural load challenges during space shuttle development
The challenges that resulted from the unique configuration of the space shuttle and capabilities developed to meet these challenges are described. The methods and the organization that were developed to perform dynamic loads analyses on the space shuttle configuration and to assess dynamic data developed after design are discussed. Examples are presented from the dynamic loads analysis of the lift-off and maximum dynamic pressure portion of ascent. Also shown are orbital flight test results, for which selected predicted responses are compared to measured data for the lift-off and high-dynamic-pressure times of ascent. These results have generally verified the design analysis. However, subscale testing was found to be deficient in predicting full-scale results in two areas: the ignition overpressure at lift-off and the aerodynamics/plume interactions at high-q boost. In these areas, the results of the flight test program were accommodated with no impact to the vehicle design
Meissner masses in the gCFL phase of QCD
We calculate the Meissner masses of gluons in neutral three-flavor color
superconducting matter for finite strange quark mass. In the CFL phase the
eissner masses are slowly varying function of the strange quark mass. For large
strange quark mass, in the so called gCFL phase, the Meissner masses of gluons
with colors and 8 become imaginary, indicating an instability.Comment: New Fig. 1 shows that also the masses of the gluons 3 and 8 are
imaginar
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