6,032 research outputs found
Pairing effect on the giant dipole resonance width at low temperature
The width of the giant dipole resonance (GDR) at finite temperature T in
Sn-120 is calculated within the Phonon Damping Model including the neutron
thermal pairing gap determined from the modified BCS theory. It is shown that
the effect of thermal pairing causes a smaller GDR width at T below 2 MeV as
compared to the one obtained neglecting pairing. This improves significantly
the agreement between theory and experiment including the most recent data
point at T = 1 MeV.Comment: 8 pages, 5 figures to be published in Physical Review
On "the authentic damping mechanism" of the phonon damping model
Some general features of the phonon damping model are presented. It is
concluded that the fits performed within this model have no physical content
Multimodal-based Diversified Summarization in Social Image Retrieval
In this paper, we describe our approach and its results for the MediaEval 2015 Retrieving Diverse Social Images task. The main strength of the proposed approach is its flexibility that permits to filter out irrelevant images, and to obtain a reli- able set of diverse and relevant images. This is done by first clustering similar images according to their textual descrip- tions and their visual content, and then extracting images from different clusters according to a measure of user’s cred- ibility. Experimental results shown that it is stable and has little fluctuation in both single-concept and multi-concept queries
Solubility isotope effects in aqueous solutions of methane
The isotope effect on the Henry's law coefficients of methane in
aqueous solution (H/D and C-12/C-13 substitution) are interpreted using
the statistical mechanical theory of condensed phase isotope effects.
The missing spectroscopic data needed for the implementation of the
theory were obtained either experimentally (infrared measurements), by
computer simulation (molecular dynamics technique), or estimated using
the Wilson's GF matrix method. The order of magnitude and sign of both
solute isotope effects can be predicted by the theory. Even a crude
estimation based on data from previous vapor pressure isotope effect
studies of pure methane at low temperature can explain the inverse
effect found for the solubility of deuterated methane in water. (C)
2002 American Institute of Physics
Derivation and assessment of strong coupling core-particle model from the Kerman-Klein-D\"onau-Frauendorf theory
We review briefly the fundamental equations of a semi-microscopic
core-particle coupling method that makes no reference to an intrinsic system of
coordinates. We then demonstrate how an intrinsic system can be introduced in
the strong coupling limit so as to yield a completely equivalent formulation.
It is emphasized that the conventional core-particle coupling calculation
introduces a further approximation that avoids what has hitherto been the most
time-consuming feature of the full theory, and that this approximation can be
introduced either in the intrinsic system, the usual case, or in the laboratory
system, our preference. A new algorithm is described for the full theory that
largely removes the difference in complexity between the two types of
calculation. Comparison of the full and approximate theories for some
representative cases provides a basis for the assessment of the accuracy of the
traditional approach. We find that for well-deformed nuclei, e.g. 157Gd and
157Tb, the core-coupling method and the full theory give similar results.Comment: revtex, 3 figures(postscript), submitted to Phys.Rev.
Application of the Kerman-Klein method to the solution of a spherical shell model for a deformed rare-earth nucleus
Core-particle coupling models are made viable by assuming that core
properties such as matrix elements of multipole and pairing operators and
excitation spectra are known independently. From the completeness relation, it
is seen, however, that these quantities are themselves algebraic functions of
the calculated core-particle amplitudes. For the deformed rare-earth nucleus
158Gd, we find that these sum rules are well-satisfied for the ground state
band, implying that we have found a self-consistent solution of the non-linear
Kerman-Klein equations.Comment: revtex and postscript, including 1 figure(postscript), submitted to
Phys.Rev.Let
Some Universal Properties for Restricted Trace Gaussian Orthogonal, Unitary and Symplectic Ensembles
Consider fixed and bounded trace Gaussian orthogonal, unitary and symplectic
ensembles, closely related to Gaussian ensembles without any constraint. For
three restricted trace Gaussian ensembles, we prove universal limits of
correlation functions at zero and at the edge of the spectrum edge. In
addition, by using the universal result in the bulk for fixed trace Gaussian
unitary ensemble, which has been obtained by Gtze and Gordin, we also
prove universal limits of correlation functions for bounded trace Gaussian
unitary ensemble.Comment: 19pages,bounded trace Gaussian ensembles are adde
Quantum magnetism and counterflow supersolidity of up-down bosonic dipoles
We study a gas of dipolar Bosons confined in a two-dimensional optical
lattice. Dipoles are considered to point freely in both up and down directions
perpendicular to the lattice plane. This results in a nearest neighbor
repulsive (attractive) interaction for aligned (anti-aligned) dipoles. We find
regions of parameters where the ground state of the system exhibits insulating
phases with ferromagnetic or anti-ferromagnetic ordering, as well as with
rational values of the average magnetization. Evidence for the existence of a
novel counterflow supersolid quantum phase is also presented.Comment: 8 pages, 6 figure
Effect of Wine Closures on the Aroma Properties of Chardonnay Wines after Four Years of Storage
The effects of wine closures on the sensory properties and aroma profiles of fresh Chardonnay wines wereevaluated after four years of bottle storage. Natural cork closure, technical cork closure, Nomacorc light,Nomacorc classic and Nomacorc premium were investigated. Among these wines sealing with differentclosures, the physicochemical parameters of the wine samples showed no significant differences, exceptthat of the free and total sulphur dioxide. Nomacorc light with the highest OTR (oxygen transition rate)had the least residual free sulphur dioxide. Most of volatiles were generally stable, and seven compounds(acetoin, 1-butanol, 2-phenylethanol, 1-pentanol, (Z)-3-hexen-1-ol, 2-nonanol and ethyl decanoate) weresignificantly affected by the wine closures. The sensory analysis revealed that cork closures preserved morefruity/flowery characters of the fresh wines after four years’ storage, as well as cork-tainted off-flavour.Two synthetic closures (Nomacorc light, Nomacorc classic) imparted some grilled attributes to the wines.Nomacorc premium highly reserved the fruity/flowery flavour without cork contamination or oxidisedtoasted characters
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