1,051 research outputs found
Baby Skyrme Model, Near-BPS Approximations and Supersymmetric Extensions
We study the baby Skyrme model as a theory that interpolates between two
distinct BPS systems. For this a near-BPS approximation can be used which,
however, involves a small deviation from each of the two BPS limits. We provide
analytical explanation and numerical support for the validity of this
approximation. We then study the set of all possible supersymmetric extensions
of the baby Skyrme model with and the particular ones with
extended supersymmetries and relate this to the above mentioned
almost-BPS approximation.Comment: 23 pages, 5 figures, v2: explanations adde
Multibaryons with strangeness, charm and bottom
Static properties of multiskyrmions with baryon numbers up to 8 are
calculated, including momenta of inertia and sigma-term. The calculations are
based on the recently suggested SU(2) rational map ansaetze. Minimization with
the help of SU(3) variational minimization program shows that these
configurations become local minima in SU(3) configuration space. The B-number
dependence of the so called flavour moment of inertia of multiskyrmions playing
an important role in the quantization procedure is close to the linear one. The
spectra of baryonic systems with strangeness, charm and bottom are considered
within a "rigid oscillator" version of the bound state soliton model. The
binding energies estimates are made for the states with largest isospin which
can appear as negatively charged nuclear fragments, as well as for states with
zero isospin - light fragments of "flavoured" nuclear matter. Our results
confirm the previously made observation that baryonic systems with charm or
bottom quantum numbers have more chance to be stable with respect to strong
interactions than strange baryonic systems.Comment: 13 pages, no figures. Submitted to Eur. Phys.
Mean field dynamics of superfluid-insulator phase transition in a gas of ultra cold atoms
A large scale dynamical simulation of the superfluid to Mott insulator
transition in the gas of ultra cold atoms placed in an optical lattice is
performed using the time dependent Gutzwiller mean field approach. This
approximate treatment allows us to take into account most of the details of the
recent experiment [Nature 415, 39 (2002)] where by changing the depth of the
lattice potential an adiabatic transition from a superfluid to a Mott insulator
state has been reported. Our simulations reveal a significant excitation of the
system with a transition to insulator in restricted regions of the trap.Comment: final version, correct Fig.7 (the published version contains wrong
fig.7 by mistake
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