600 research outputs found
Charged three-body system with arbitrary masses near conformal invariance
Within an adiabatic approximation to the three-body Coulomb system, we study
the strength of the leading order conformaly invariant attractive dipole
interaction produced when a slow charged particle (with mass ) is
captured by the first excited state of a dimer [with individual masses and
charges ) and ()]. The approach leads to a universal
mass-charge critical condition for the existence of three-body level
condensation, , as well as the ratio between the geometrically scaled energy levels.
The resulting expressions can be relevant in the analysis of recent
experimental setups with charged three-body systems, such as the interactions
of excitons, or other matter-antimatter dimers, with a slow charged particle.Comment: 5 pages, 1 figure, to appear in Physical Review
Critical numbers of attractive Bose-condensed atoms in asymmetric traps
The recent Bose-Einstein condensation of ultracold atoms with attractive
interactions led us to consider the novel possibility to probe the stability of
its ground state in arbitrary three-dimensional harmonic traps. We performed a
quantitative analysis of the critical number of atoms through a full numerical
solution of the mean field Gross-Pitaevskii equation. Characteristic limits are
obtained for reductions from three to two and one dimensions, in perfect
cylindrical symmetries as well as in deformed ones.Comment: 5 pages, 3 figures. To appear in Phys. Rev.
Path Dependence of the Quark Nonlocal Condensate within the Instanton Model
Within the instanton liquid model, we study the dependence of the gauge
invariant two--point quark correlator on the path used to perform the color
parallel transport between two points in the Euclidean space.Comment: 4 pages, 5 figure
Nucleon-nucleon scattering within a multiple subtractive renormalization approach
A methodology to renormalize the nucleon-nucleon interaction, using a
recursive multiple subtraction approach to construct the kernel of the
scattering equation, is presented. We solve the subtracted scattering equation
with the next-leading-order (NLO) and next-to-next-leading-order (NNLO)
interactions. The results are presented for all partial waves up to ,
fitted to low-energy experimental data. In our renormalizaton group invariant
method, when introducing the NLO and NNLO interactions, the subtraction energy
emerges as a renormalization scale and the momentum associated with it comes to
be about the QCD scale (), irrespectively to the partial wave.Comment: Final versio
Two definitions of the electric polarizability of a bound system in relativistic quantum theory
For the electric polarizability of a bound system in relativistic quantum
theory, there are two definitions that have appeared in the literature. They
differ depending on whether or not the vacuum background is included in the
system. A recent confusion in this connection is clarified
Liquid-Gas phase transition in Bose-Einstein Condensates with time evolution
We study the effects of a repulsive three-body interaction on a system of
trapped ultra-cold atoms in Bose-Einstein condensed state. The stationary
solutions of the corresponding wave non-linear Schr\"{o}dinger equation
suggest a scenario of first-order liquid-gas phase transition in the condensed
state up to a critical strength of the effective three-body force. The time
evolution of the condensate with feeding process and three-body recombination
losses has a new characteristic pattern. Also, the decay time of the dense
(liquid) phase is longer than expected due to strong oscillations of the
mean-square-radius.Comment: 4 eps-figure
Liquid-Gas phase transition in Bose-Einstein Condensates
We study the effects of a repulsive three-body interaction on a system of
trapped ultra-cold atoms in a Bose-Einstein condensed state. The corresponding
wave non-linear Schr\"{o}dinger equation is solved numerically and also by
a variational approach. A first-order liquid-gas phase transition is observed
for the condensed state up to a critical strength of the effective three-body
force.Comment: 4 pages, 3 figure
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