A phase conjugate mirror inspired approach for building cloaking structures with left-handed materials

In this paper, we propose and examine a new cloaking method, which was inspired by the close correspondence between a phase conjugate mirror and the interface between a pair of matched right-handed material (RHM) and left-handed material (LHM) media. Using this method, we show that a symmetric conducting shell embedded in the interface junction of an isotropic RHM layer and an isotropic negative index or LHM layer can serve as a limited cloaking structure. The proposed structure presents an anomalously small scattering cross-section to an incident propagating electromagnetic (EM) field. The interior of the shell can be used to shield small objects from interrogation. We report the results of 2D finite-element-method (FEM) simulations that were performed to verify the principle, and discuss the limitations of the proposed structure

DJpsiFDC: an event generator for the process gg→J/ψJ/ψgg\to J/\psi J/\psi at LHC

DJpsiFDC is an event generator package for the process $gg\to J/\psi J/\psi$. It generates events for primary leading-order $2\to 2$ processes. The package could generate a LHE document and this document could easily be embedded into detector simulation software frameworks. The package is produced in Fortran codes.Comment: 10 pages, 3 figure

Application of Blind Deblurring Reconstruction Technique to SPECT Imaging

An SPECT image can be approximated as the convolution of the ground truth spatial radioactivity with the system point spread function (PSF). The PSF of an SPECT system is determined by the combined effect of several factors, including the gamma camera PSF, scattering, attenuation, and collimator response. It is hard to determine the SPECT system PSF analytically, although it may be measured experimentally. We formulated a blind deblurring reconstruction algorithm to estimate both the spatial radioactivity distribution and the system PSF from the set of blurred projection images. The algorithm imposes certain spatial-frequency domain constraints on the reconstruction volume and the PSF and does not otherwise assume knowledge of the PSF. The algorithm alternates between two iterative update sequences that correspond to the PSF and radioactivity estimations, respectively. In simulations and a small-animal study, the algorithm reduced image blurring and preserved the edges without introducing extra artifacts. The localized measurement shows that the reconstruction efficiency of SPECT images improved more than 50% compared to conventional expectation maximization (EM) reconstruction. In experimental studies, the contrast and quality of reconstruction was substantially improved with the blind deblurring reconstruction algorithm