11,879 research outputs found
Quasideuteron states with deformed core
The M1 transitions between low-lying T=1 and T=0 states in deformed odd-odd
N=Z nuclei are analyzed in the frames of the rotor-plus-particle model. Using
the representation of an explicit coupling of angular momenta we show that
strong coupling of the quasideuteron configurations to the axially deformed
core results in a distribution of the total 0+ --> 1+ strength among a few
low-lying 1+ states. Simple analytical formulae for B(M1) values are derived.
The realization of the M1 sum rule for the low-lying 1+,T=0 states is
indicated. The calculated B(M1) values are found to be in good agreement with
experimental data and reveal specific features of collectivity in odd-odd N=Z
nuclei.Comment: 11 pages, 1 figure, LaTe
Quasideuteron configurations in 46V and 58Cu
The data on low spin states in the odd-odd nuclei 46V and 58Cu investigated
with the 46Ti(p,ngamma)46V, 32S(16O,pn)46V and 58Ni(p,ngamma)58Cu reactions at
the FN-TANDEM accelerator in Cologne are reported. The states containing large
quasideuteron components are identified from the strong isovector M1
transitions, from shell model calculations and from experimental data for
low-lying states.Comment: 6 pages, 3 figures, proceedings of the "Nuclear Structure 2000"
conference, East Lansing, Michigan, USA, August 15-19, 2000; to appear in
Nucl. Phys.
Low-Spin Spectroscopy of 50Mn
The data on low spin states in the odd-odd nucleus 50Mn investigated with the
50Cr(p,ngamma)50Mn fusion evaporation reaction at the FN-TANDEM accelerator in
Cologne are reported. Shell model and collective rotational model
interpretations of the data are given.Comment: 7 pages, 2 figures, to be published in the proceedings of the
"Bologna 2000 - Structure of the Nucleus at the Dawn of the Century"
Conference, (Bologna, Italy, May 29 - June 3, 2000
Deep Autoencoder for Combined Human Pose Estimation and body Model Upscaling
We present a method for simultaneously estimating 3D human pose and body
shape from a sparse set of wide-baseline camera views. We train a symmetric
convolutional autoencoder with a dual loss that enforces learning of a latent
representation that encodes skeletal joint positions, and at the same time
learns a deep representation of volumetric body shape. We harness the latter to
up-scale input volumetric data by a factor of , whilst recovering a
3D estimate of joint positions with equal or greater accuracy than the state of
the art. Inference runs in real-time (25 fps) and has the potential for passive
human behaviour monitoring where there is a requirement for high fidelity
estimation of human body shape and pose
Coupling of Surface and Volume Dipole Oscillations in C-60 Molecules
We first give a short review of the ``local-current approximation'' (LCA),
derived from a general variation principle, which serves as a semiclassical
description of strongly collective excitations in finite fermion systems
starting from their quantum-mechanical mean-field ground state. We illustrate
it for the example of coupled translational and compressional dipole
excitations in metal clusters. We then discuss collective electronic dipole
excitations in C molecules (Buckminster fullerenes). We show that the
coupling of the pure translational mode (``surface plasmon'') with
compressional volume modes in the semiclasscial LCA yields semi-quantitative
agreement with microscopic time-dependent density functional (TDLDA)
calculations, while both theories yield qualitative agreement with the recent
experimental observation of a ``volume plasmon''.Comment: LaTeX, 12 pages, 5 figures (8 *.eps files); Contribution to XIV-th
Nuclear Physics Workshop at Kazimierz Dolny, Poland, Sept. 26-29, 200
The gas–liquid phase-transition singularities in the framework of the liquid-state integral equation formalism
6 pages, 4 figures.-- PACS: 64.70.Fx; 65.20.+w;
02.30.Rz; 62.10.+sThe singularities of various liquid-state integral equations derived from the Ornstein–Zernike relation and its temperature derivatives, have been investigated in the liquid–vapor transition region. As a general feature, it has been found that the existence of a nonsolution curve on the vapor side of the phase diagram, on which both the direct and the total correlation functions become complex—with a finite isothermal compressibility—also corresponds to the locus of points where the constant-volume heat capacity diverges, in consonance with a divergence of the temperature derivative of the correlation functions. In contrast, on the liquid side of the phase diagram one finds that a true spinodal (a curve of diverging isothermal compressibilities) is reproduced by the Percus–Yevick and Martynov–Sarkisov integral equations, but now this curve corresponds to states with finite heat capacity. On the other hand, the hypernetted chain approximation exhibits a nonsolution curve with finite compressibilities and heat capacities in which, as temperature is lowered, the former tends to diverge.E.L. acknowledges financial support of the Dirección
General de Investigación Científica y Técnica under Grant
No. FIS2004-02954-C03-01. This work has been carried out
under the auspices of the exchange agreement between the
Consejo Superior de Investigaciones Científicas and the Russian
Academy of Sciencies, which supported the exchange
visits of E.L. and G.S. in the past two years.Peer reviewe
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