2,549 research outputs found
Contextual-based Image Inpainting: Infer, Match, and Translate
We study the task of image inpainting, which is to fill in the missing region
of an incomplete image with plausible contents. To this end, we propose a
learning-based approach to generate visually coherent completion given a
high-resolution image with missing components. In order to overcome the
difficulty to directly learn the distribution of high-dimensional image data,
we divide the task into inference and translation as two separate steps and
model each step with a deep neural network. We also use simple heuristics to
guide the propagation of local textures from the boundary to the hole. We show
that, by using such techniques, inpainting reduces to the problem of learning
two image-feature translation functions in much smaller space and hence easier
to train. We evaluate our method on several public datasets and show that we
generate results of better visual quality than previous state-of-the-art
methods.Comment: ECCV 2018 camera read
Analyzing eta' photoproduction data on the proton at energies of 1.5--2.3 GeV
The recent high-precision data for the reaction at
photon energies in the range 1.5--2.3 GeV obtained by the CLAS collaboration at
the Jefferson Laboratory have been analyzed within an extended version of the
photoproduction model developed previously by the authors based on a
relativistic meson-exchange model of hadronic interactions [Phys. Rev. C
\textbf{69}, 065212 (2004)]. The photoproduction can be described quite
well over the entire energy range of available data by considering ,
, , and resonances, in addition to the -channel
mesonic currents. The observed angular distribution is due to the interference
between the -channel and the nucleon - and -channel resonance
contributions. The resonances are required to reproduce some of the
details of the measured angular distribution. For the resonances considered,
our analysis yields mass values compatible with those advocated by the Particle
Data Group. We emphasize, however, that cross-section data alone are unable to
pin down the resonance parameters and it is shown that the beam and/or target
asymmetries impose more stringent constraints on these parameter values. It is
found that the nucleonic current is relatively small and that the
coupling constant is not expected to be much larger than 2.Comment: Revised version based on revised (finalized) CLAS data (14 pages, 10
figures, RevTeX4
N-Body Nuclear Forces at Short Distances in Holographic QCD
We provide a calculation of N-body (N>2) nucleon interactions at short
distances in holographic QCD. In the Sakai-Sugimoto model of large N_c massless
QCD, N baryons are described by N Yang-Mills instantons in 5 spacetime
dimensions. We compute a classical short distance interaction hamiltonian for N
'tHooft instantons. This corresponds to N baryons sharing identical classical
spins and isospins. We find that genuine N-body nuclear forces turn out to
vanish for N>2, at the leading order. This suggests that classical N-body
forces are always suppressed compared with 2-body forces.Comment: 4 page
Comment on "Valence QCD: Connecting QCD to the Quark Model"
I criticize certain conclusions about the physics of hadrons drawn from a
"valence QCD" approximation to QCD.Comment: 12 pages, 8 figures; some minor improvements made to the tex
Possible Molecular Structure of the Newly Observed Y(4260)
We suggest that the newly observed resonance Y(4260) is a
molecule, which is an isovector. In this picture, we can easily interpret why
has a larger rate than which
has not been observed, and we also predict existence of the other two
components of the isotriplet and another two possible partner states which may
be observed in the future experiments. A direct consequence of this structure
is that for this molecular structure mode is more
favorable than which may have a larger fraction if
other proposed structures prevail.Comment: 5 pages, 2 figures. Some descriptions changed, more references added
and typos corrected. Published version in PR
Temperature- and Magnetic-Field-Dependent Optical Properties of Heavy Quasiparticles in YbIr2Si2
We report the temperature- and magnetic-field-dependent optical conductivity
spectra of the heavy electron metal YbIrSi. Upon cooling below the
Kondo temperature (), we observed a typical charge dynamics that is
expected for a formation of a coherent heavy quasiparticle state. We obtained a
good fitting of the Drude weight of the heavy quasiparticles by applying a
modified Drude formula with a photon energy dependence of the quasiparticle
scattering rate that shows a similar power-law behavior as the temperature
dependence of the electrical resistivity. By applying a magnetic field of 6T
below , we found a weakening of the effective dynamical mass
enhancement by about 12% in agreement with the expected decrease of the
-conduction electron hybridization on magnetic field.Comment: 5 pages, 4 figures. to be published in Journal of the Physical
Society of Japan Vol. 79 (2010) No. 1
Far-infrared optical conductivity of CeCu2Si2
Journal ref.: J. Phys.: Condens. Matter 25, 065602 (2013): We investigated
the optical reflectivity of the heavy-fermion metal CeCu2Si2 in the energy
range 3 meV - 30 eV for temperatures between 4K - 300K. The results for the
charge dynamics indicate a behavior that is expected for the formation of a
coherent heavy quasiparticle state: Upon cooling the spectra of the optical
conductivity indicate a narrowing of the coherent response. Below temperatures
of 30 K a considerable suppression of conductivity evolves below a peak
structure at 13 meV. We assign this gap-like feature to strong electron
correlations due to the 4f-conduction electron hybridization.Comment: 7 pages, 3 figure
Stochastic Process Associated with Traveling Wave Solutions of the Sine-Gordon Equation
Stochastic processes associated with traveling wave solutions of the
sine-Gordon equation are presented. The structure of the forward Kolmogorov
equation as a conservation law is essential in the construction and so is the
traveling wave structure. The derived stochastic processes are analyzed
numerically. An interpretation of the behaviors of the stochastic processes is
given in terms of the equation of motion.Comment: 12 pages, 9 figures; corrected typo
Production of , , and in hadronic decays
A coherent study of the production of (, 2, 3 corresponding to
, , and ) in is
reported based on a previously proposed glueball and nonet mixing
scheme, and a factorization for the decay of , where
denotes the isoscalar vector mesons and , and denotes
pseudoscalar mesons. The results show that the decays are very
sensitive to the structure of those scalar mesons, and suggest a glueball in
the GeV region, in line with Lattice QCD. The presence of significant
glueball mixings in the scalar wavefunctions produces peculiar patterns in the
branching ratios for , which are in good agreement
with the recently published experimental data from the BES collaboration.Comment: Version accepted by PRD; Numerical results in Tab IV and VI changed
due to correction of an error in quoting an experimental datum; Conclusion is
not change
A new look at scalar mesons
Light scalar mesons are found to fit rather well a diquark-antidiquark
description. The resulting nonet obeys mass formulae which respect, to a good
extent, the OZI rule. OZI allowed strong decays are reasonably reproduced by a
single amplitude describing the switch of a qbar-q pair, which transforms the
state into two colourless pseudoscalar mesons. Predicted heavy states with one
or more quarks replaced by charm or beauty are briefly described; they should
give rise to narrow states with exotic quantum numbers.Comment: 4 pages, 1 figure, misprints corrected, references added, accepted
for publication in Phys. Rev. Let
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