13,251 research outputs found
Characterizing Scattering by 3-D Arbitrarily Shaped Homogeneous Dielectric Objects Using Fast Multipole Method
Electromagnetic scattering by 3-D arbitrarily shaped homogeneous dielectric objects is characterized. In the analysis, the method of moments is first employed to solve the combined field integral equation for scattering properties of these three-dimensional homogeneous dielectric objects of arbitrary shape. The fast multipole method, and the multi-level fast multipole algorithm are implemented into our codes for matrix-vector manipulations. Specifically, four proposals are made and discussed to increase convergence and accuracy of iterative procedures (conjugate gradient method). Numerical results are obtained using various methods and compared to each other.Singapore-MIT Alliance (SMA
Electromagnetic Scattering by Open-Ended Cavities: An Analysis Using Precorrected-FFT Approach
In this paper, the precorrected-FFT method is used to solve the electromagnetic scattering from two-dimensional cavities of arbitrary shape. The integral equation is discretized by the method of moments and the resultant matrix equation is solved iteratively by the generalized conjugate residual method. Instead of directly computing the matrix-vector multiplication, which requires N² operations, this approach reduces the computation complexity to O(N log N) as well as avoids the storage of large matrices. At the same time, a technique known as the complexifying k is applied to accelerate the convergence of the iterative method in solving this resonance problem. Some examples are considered and excellent agreements of radar cross sections between these computed using the present method and those from the direct solution are observed, demonstrating the feasibility and efficiency of the present method.Singapore-MIT Alliance (SMA
Study of the decay due to the bound state
We study the decay by taking into account the
-wave contributions from the pseudoscalar meson--pseudoscalar meson
interactions within the unitary coupled-channel approach, where the
bound state is dynamically generated. In addition, the contribution from the
intermediate resonance , with , is also
considered. Our results show that there is a clear peak around ~MeV in
the invariant mass distribution, which could be associated with
the bound state. The future precise measurements of the process at the Belle II and LHCb experiments could be,
therefore, used to check the existence of the bound state, and to
deepen our understanding of the hadron-hadron interactions.Comment: 8 pages, 8 figure
Performance Analysis of Metamaterials With Two-dimensional Isotropy
A two-dimensional isotropic metamaterials formed by crossed split-ring resonators (CSRRs) are studied in this paper. The effective characteristic parameters of this media are determined by quasi-static Lorentz theory. The induced current distributions of a single CSRR at the resonant frequency are presented. Moreover, the dependence of the resonant frequency on the dimensions of single CSRR and the spaces of the array are also discussed.Singapore-MIT Alliance (SMA
The in the single Cabibbo-suppressed process
In this work, we have investigated the Cabibbo-suppressed process , by taking into account the intermediate scalar state
, which could be dynamically generated from the -wave
pseudoscalar-pseudoscalar interaction within the chiral unitary approach. We
have calculated the invariant mass distribution, and found that
there is a significant structure associated to the . We have also
roughly estimated the branching fraction . We encourage our experimental colleagues to measure the
process for searching for the state
signal in this reaction.Comment: 8 pages, 5 figure
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