6,636 research outputs found
Existence of One-Body Barrier Revealed in Deep Sub-Barrier Fusion
Based on the adiabatic picture for heavy-ion reactions, in which the neck
formation in the one-body system is taken into account, we propose a two-step
model for fusion cross sections at deep subbarrier energies. This model
consists of the capture process in the two-body potential pocket, which is
followed by the penetration of the adiabatic one-body potential to reach a
compound state after the touching configuration. We describe the former process
with the coupled-channels framework, while the latter with the WKB
approximation by taking into account the coordinate dependent inertia mass. The
effect of the one-body barrier is important at incident energies below the
potential energy at the touching configuration. We show that this model well
accounts for the steep fall-off phenomenon of fusion cross sections at deep
subbarrier energies for the Ni+Ni and Ni+Ni
reactions.Comment: 4 pages, 3 figure
Entanglement of Indistinguishable Particles
We present a general criterion for entanglement of N indistinguishable
particles decomposed into arbitrary s subsystems based on the unambiguous
measurability of correlation. Our argument provides a unified viewpoint on the
entanglement of indistinguishable particles, which is still unsettled despite
various proposals made mainly for the s = 2 case. Even though entanglement is
defined only with reference to the measurement setup, we find that the
so-called i.i.d. states form a special class of bosonic states which are
universally separable.Comment: 6 pages, 3 figures, major revisio
Non-Gaussianity, Spectral Index and Tensor Modes in Mixed Inflaton and Curvaton Models
We study non-Gaussianity, the spectral index of primordial scalar
fluctuations and tensor modes in models where fluctuations from the inflaton
and the curvaton can both contribute to the present cosmic density
fluctuations. Even though simple single-field inflation models generate only
tiny non-Gaussianity, if we consider such a mixed scenario, large
non-Gaussianity can be produced. Furthermore, we study the inflationary
parameters such as the spectral index and the tensor-to-scalar ratio in this
kind of models and discuss in what cases models predict the spectral index and
tensor modes allowed by the current data while generating large
non-Gaussianity, which may have many implications for model-buildings of the
inflationary universe.Comment: 40 pages, 16 figures, discussions added, references adde
Effect of stripe order strength for the Nernst effect in La_{2-x}Sr_xCu_4 single crystals
We have precisely measured the Nernst effect in Nd-doped
LaSrCuO single crystals with controlling the strength
(stability) of the stripe order. We found that the onset temperature
, where the Nernst signal starts increasing, does not change
conspicuously in spite of Nd-doping. At low temperatures, on the other hand,
the absolute value of the Nernst signal is strongly suppressed in accordance
with the strength of the stripe order. These results imply that the fluctuation
of (charge) stripe order enhances the Nernst signal below at high
temperatures, and then the stripe order enhanced by Nd-doping suppresses the
superconducting fluctuation to reduce the Nernst signal at low temperatures. We
also observed an increase of the Nernst signal below the charge order
temperature which is observed in diffraction measurement.Comment: 3pages, 2figure
Static and Dynamic Chain Structures in the Mean-Field Theory
We give a brief overview of recent work examining the presence of
-clusters in light nuclei within the Skyrme-force Hartree-Fock model.
Of special significance are investigations into -chain structures in
carbon isotopes and O. Their stability and possible role in fusion
reactions are examined in static and time-dependent Hartree-Fock calculations.
We find a new type of shape transition in collisions and a centrifugal
stabilization of the chain state in a limited range of angular
momenta. No stabilization is found for the chain.Comment: Fusionn 11 Conference, St. Malo, France, 201
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