58,329 research outputs found
Search for -cluster states in even-even Cr isotopes
The structure is investigated in even-even Cr
isotopes from the viewpoint of the local potential model. The comparison of
values for even-even Cr isotopes and even-even
isobars indicates that Cr and Cr are the most favorable even-even
Cr isotopes for -clustering. The ground state bands of the two Cr
isotopes are calculated through a local potential with
two variable parameters. The calculated spectra give a very good description of
most experimental Cr and Cr levels. The reduced -widths,
rms intercluster separations and transition rates are determined for
the ground state bands. The calculations reproduce the order of magnitude of
the available experimental values without using effective charges and
indicate that the first members of the ground state bands present a stronger
-cluster character. The volume integral per nucleon pair and rms radius
obtained for the Ti potential are consistent with those reported
previously in the analysis of elastic scattering on Ti
The Dyer-Roeder relation in a universe with particle production
We have obtained analytical exact solutions of the Dyer-Roeder equation in a
cosmological model where creation of particles occurs at the expenses of the
gravitational field. We discussed the influences of inhomogeneities in the path
of a light beam on the apparent diameter of astrophysical objects and consider
both redshift independent as redshift dependent distributions of the
inhomogeneities.Comment: 7 pages, 4 figures. Accepted to be published in the Astronomy and
Astrophysics Journa
Three path interference using nuclear magnetic resonance: a test of the consistency of Born's rule
The Born rule is at the foundation of quantum mechanics and transforms our
classical way of understanding probabilities by predicting that interference
occurs between pairs of independent paths of a single object. One consequence
of the Born rule is that three way (or three paths) quantum interference does
not exist. In order to test the consistency of the Born rule, we examine
detection probabilities in three path intereference using an ensemble of
spin-1/2 quantum registers in liquid state nuclear magnetic resonance (LSNMR).
As a measure of the consistency, we evaluate the ratio of three way
interference to two way interference. Our experiment bounded the ratio to the
order of , and hence it is consistent with Born's rule.Comment: 11 pages, 4 figures; Improved presentation of figures 1 and 4,
changes made in section 2 to better describe the experiment, minor changes
throughout, and added several reference
Correlated electrons systems on the Apollonian network
Strongly correlated electrons on an Apollonian network are studied using the
Hubbard model. Ground-state and thermodynamic properties, including specific
heat, magnetic susceptibility, spin-spin correlation function, double occupancy
and one-electron transfer, are evaluated applying direct diagonalization and
quantum Monte Carlo. The results support several types of magnetic behavior. In
the strong-coupling limit, the quantum anisotropic spin 1/2 Heisenberg model is
used and the phase diagram is discussed using the renormalization group method.
For ferromagnetic coupling, we always observe the existence of long-range
order. For antiferromagnetic coupling, we find a paramagnetic phase for all
finite temperatures.Comment: 7 pages, 8 figure
A note on the infrared behavior of the compactified Ginzburg--Landau model in a magnetic field
We consider the Euclidean large- Ginzburg--Landau model in dimensions,
() of them being compactified. For D=3, the system can be supposed
to describe, in the cases of d=1, d=2, and d=3, respectively, a superconducting
material in the form of a film, of an infinitely long wire having a rectangular
cross-section and of a brick-shaped grain. We investigate the fixed-point
structure of the model, in the presence of an external magnetic field. An
infrared-stable fixed points is found, which is independent of the number of
compactified dimensions. This generalizes previous work for type-II
superconducting filmsComment: LATEX, 6 pages no figures. arXiv admin note: 80% of text overlaps
with arXiv:1102.139
Information-Entropic Measure of Energy-Degenerate Kinks in Two-Field Models
We investigate the existence and properties of kink-like solitons in a class
of models with two interacting scalar fields. In particular, we focus on models
that display both double and single-kink solutions, treatable analytically
using the Bogomol'nyi--Prasad--Sommerfield bound (BPS). Such models are of
interest in applications that include Skyrmions and various
superstring-motivated theories. Exploring a region of parameter space where the
energy for very different spatially-bound configurations is degenerate, we show
that a newly-proposed momentum-space entropic measure called Configurational
Entropy (CE) can distinguish between such energy-degenerate spatial profiles.
This information-theoretic measure of spatial complexity provides a
complementary perspective to situations where strictly energy-based arguments
are inconclusive
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