2,644,437 research outputs found
Static-static-light-light tetraquarks in lattice QCD
I report on a lattice computation of the energy of a system of two light
quarks and two static antiquarks as a function of the separation of the static
antiquarks. In terms of hadrons such a system corresponds to a pair of B mesons
and its energy to the hadronic potential. I present selected results for
different isospin, spin and parity combinations of the individual B mesons
mainly focusing on those channels relevant to determine, whether two B mesons
may form a bound tetraquark state.Comment: 6 pages, 1 figure, talk given at "Excited QCD 2011", February 20-25
2011, Les Houches, Franc
Static aeroelastic program
Set of programs computes geometric, mass, aerodynamic, and structural effects on fighter and transport type aircraft at subsonic and supersonic speeds
Asymptotically Static Universe
We consider a cosmology in which the final stage of the Universe is neither
accelerating nor decelerating, but approaches an asymptotic state where the
scale factor becomes a constant value. In order to achieve this, we first bring
in a scale factor with the desired property and then determine the details of
the energy contents as a result of the cosmological evolution equations. We
show that such a scenario can be realized if we introduce a generalized quintom
model which consists of a scalar field and a phantom with a {\it negative}
cosmological constant term. The standard cold dark matter with is also
introduced. This is possible basically due to the balance between the matter
and the {\it negative} cosmological constant which tend to attract and scalar
field and phantom which repel in the asymptotic region. The stability analysis
shows that this asymptotic solution is classically stable.Comment: Final version published in PR
Static intervortex forces
A point particle approximation to the classical dynamics of well separated
vortices of the abelian Higgs model is developed. A static vortex is
asymptotically identical to a solution of the linearized field theory (a
Klein-Gordon/Proca theory) in the presence of a singular point source at the
vortex centre. It is shown that this source is a composite scalar monopole and
magnetic dipole, and the respective charges are determined numerically for
various values of the coupling constant. The interaction potential of two well
separated vortices is computed by calculating the interaction Lagrangian of two
such point sources in the linear theory. The potential is used to model type II
vortex scattering.Comment: Much shorter (10 pages) published version, new titl
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