22,194 research outputs found
Charmless Two-body decays In Soft-Collinear-Effective-Theory
We provide the analysis of charmless two-body decays under the
framework of the soft-collinear-effective-theory (SCET), where denotes a
light vector (pseudoscalar) meson. Besides the leading power contributions,
some power corrections (chiraly enhanced penguins) are also taken into account.
Using the current available and experimental data on
branching fractions and CP asymmetry variables, we find two kinds of solutions
in fit for the 16 non-perturbative inputs which are essential in the
87 and decay channels. Chiraly enhanced penguins can change
several charming penguins sizably, since they share the same topology. However,
most of the other non-perturbative inputs and predictions on branching ratios
and CP asymmetries are not changed too much. With the two sets of inputs, we
predict the branching fractions and CP asymmetries of other modes especially
decays. The agreements and differences with results in QCD
factorization and perturbative QCD approach are analyzed. We also study the
time-dependent CP asymmetries in channels with CP eigenstates in the final
states and some other channels such as and
. In the perturbative QCD approach, the
penguins in annihilation diagrams play an important role. Although
they have the same topology with charming penguins in SCET, there are many
differences between the two objects in weak phases, magnitudes, strong phases
and factorization properties.Comment: 34 pages, revtex, 2 figures, published at PR
Hollow Gaussian Schell-model beam and its propagation
In this paper, we present a new model, hollow Gaussian-Schell model beams
(HGSMBs), to describe the practical dark hollow beams. An analytical
propagation formula for HGSMBs passing through a paraxial first-order optical
system is derived based on the theory of coherence. Based on the derived
formula, an application example showing the influence of spatial coherence on
the propagation of beams is illustrated. It is found that the beam propagating
properties of HGSMBs will be greatly affected by their spatial coherence. Our
model provides a very convenient way for analyzing the propagation properties
of partially coherent dark hollow beams.Comment: 13pages, 2 figure
Guest Editorial Special Issue on Graph-Powered Machine Learning for Internet of Things
Internet of Things (IoT) refers to an ecosystem where applications and services are driven by data collected from devices interacting with each other and the physical world. Although IoT has already brought spectacular benefits to human society, the progress is actually not as fast as expected. From network structures to control flow graphs, IoT naturally generates an unprecedented volume of graph data continuously, which stimulates fertilization and making use of advanced graph-powered methods on the diverse, dynamic, and large-scale graph IoT data
Transition of the dark energy equation of state in an interacting holographic dark energy model
A model of holographic dark energy with an interaction with matter fields has
been investigated. Choosing the future event horizon as an IR cutoff, we have
shown that the ratio of energy densities can vary with time. With the
interaction between the two different constituents of the universe, we observed
the evolution of the universe, from early deceleration to late time
acceleration. In addition, we have found that such an interacting dark energy
model can accommodate a transition of the dark energy from a normal state where
to phantom regimes. Implications of interacting dark energy
model for the observation of dark energy transition has been discussed.Comment: revised version, references added. Accepted for publication in PL
Synchronization of stochastic genetic oscillator networks with time delays and Markovian jumping parameters
The official published version of the article can be found at the link below.Genetic oscillator networks (GONs) are inherently coupled complex systems where the nodes indicate the biochemicals and the couplings represent the biochemical interactions. This paper is concerned with the synchronization problem of a general class of stochastic GONs with time delays and Markovian jumping parameters, where the GONs are subject to both the stochastic disturbances and the Markovian parameter switching. The regulatory functions of the addressed GONs are described by the sector-like nonlinear functions. By applying up-to-date ‘delay-fractioning’ approach for achieving delay-dependent conditions, we construct novel matrix functional to derive the synchronization criteria for the GONs that are formulated in terms of linear matrix inequalities (LMIs). Note that LMIs are easily solvable by the Matlab toolbox. A simulation example is used to demonstrate the synchronization phenomena within biological organisms of a given GON and therefore shows the applicability of the obtained results.This work was supported in part by the Biotechnology and Biological Sciences Research Council (BBSRC) of the UK under Grants BB/C506264/1 and 100/EGM17735, the Royal Society of the UK, the National Natural Science Foundation of China under Grant 60804028, the Teaching and Research Fund for Excellent Young Teachers at Southeast University of China, the International Science and Technology Cooperation Project of China under Grant 2009DFA32050, and the Alexander von Humboldt Foundation of Germany
5-Methylisoxazole-4-carboxylic acid
In the title compound, C5H5NO3, the molecule lies on a crystallographic mirror plane with one half-molecule in the asymmetric unit. An intramolecular C—H⋯O interaction is present. In the crystal, strong intermolecular O—H⋯N hydrogen bonds result in the formation of a linear chain structure along [100], and there are also weak C—H⋯O hydrogen bonds between the chains which help to stabilize the crystal packing
Isospin dependence of projectile-like fragment production at intermediate energies
The cross sections of fragments produced in 140 MeV Ca + Be
and Ni + Be reactions are calculated by the statistical
abration-ablation(SAA) model and compared to the experimental results measured
at the National Superconducting Cyclotron Laboratory (NSCL) at Michigan State
University. The fragment isotopic and isotonic cross section distributions of
Ca and Ca, Ni and Ni, Ca and Ni, and
Ca and Ni are compared and the isospin dependence of the
projectile fragmentation is studied. It is found that the isospin dependence
decreases and disappears in the central collisions. The shapes of the fragment
isotopic and isotonic cross section distributions are found to be very similar
for symmetric projectile nuclei. The shapes of the fragment isotopic and
isotonic distributions of different asymmetric projectiles produced in
peripheral reactions are found very similar. The similarity of the
distributions are related to the similar proton and neutron density
distributions inside the nucleus in framework of the SAA model.Comment: 7 pages, 4 figures; to be published in Phys Rev
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