Finite Mass Effect on Two Photon Processes in Hydrogenic Systems: Effective Scalar Photon Interaction

We consider a hydrogenic system with a nucleus of finite mass. The coupling of the radiation field to the center of mass motion gives rise to an effective scalar type coupling. This induced scalar photon interaction emerges as a correction in competition with the usual multipole interactions. This effect is particularly important in positronium where the electric quadrupole interaction is totally suppressed. We illustrate this effect with the two-photon decay of metastable hydrogenic systems.Comment: 12 pages, Latex, no figure. Version to appear in Phys. Lett.

Perturbative Scattering Phase Shifts in One-Dimension: Closed-form Results

A simple closed form expression is obtained for the scattering phase shift perturbatively to any given order in effective one-dimensional problems. The result is a hierarchical scheme, expressible in quadratures, requiring only knowledge of the zeroth order solution and the perturbation potential.Comment: 10 pages in REVTe

Efficient Conditional Proxy Re-encryption with Chosen-Ciphertext Security

Recently, a variant of proxy re-encryption, named conditional proxy re-encryption (C-PRE), has been introduced. Compared with traditional proxy re-encryption, C-PRE enables the delegator to implement fine-grained delegation of decryption rights, and thus is more useful in many applications. In this paper, based on a careful observation on the existing definitions and security notions for C-PRE, we reformalize more rigorous definition and security notions for C-PRE. We further propose a more efficient C-PRE scheme, and prove its chosenciphertext security under the decisional bilinear Diffie-Hellman (DBDH) assumption in the random oracle model. In addition, we point out that a recent C-PRE scheme fails to achieve the chosen-ciphertext security

A dynamical chiral bag model

We study a dynamical chiral bag model, in which massless fermions are confined within an impenetrable but movable bag coupled to meson fields. The self-consistent motion of the bag is obtained by solving the equations of motion exactly assuming spherical symmetry. When the bag interacts with an external meson wave we find three different kinds of resonances: {\it fermionic}, {\it geometric}, and $\sigma$-resonances. We discuss the phenomenological implications of our results.Comment: Two columns, 11 pages, 9 figures. Submitted to Physical Review

Coherent dynamics of Bose-Einstein condensates in high-finesse optical cavities

We study the mutual interaction of a Bose-Einstein condensed gas with a single mode of a high-finesse optical cavity. We show how the cavity transmission reflects condensate properties and calculate the self-consistent intra-cavity light field and condensate evolution. Solving the coupled condensate-cavity equations we find that while falling through the cavity, the condensate is adiabatically transfered into the ground state of the periodic optical potential. This allows time dependent non-destructive measurements on Bose-Einstein condensates with intriguing prospects for subsequent controlled manipulation.Comment: 5 pages, 5 figures; revised version: added reference

Real-time reverse transcriptase PCR assay for detection of human metapneumoviruses from all known genetic lineages

The discovery of human metapneumovirus and its implications for respiratory tract disease have emphasized the need for a sensitive, specific, and rapid assay to detect this virus in a clinical setting. It recently became clear that human metapneumovirus can be grouped into at least four genetic lineages. Previously described assays for the detection of human metapneumovirus were developed by using limited sequence information and failed to detect viruses from all four genetic lineages with comparable sensitivities. Here we describe the development and evaluation of a real-time reverse transcriptase PCR assay that detects human metapneumovirus from the four known genetic lineages with equal specificities and sensitivities

Mean-field description of ground-state properties of drip-line nuclei. (I) Shell-correction method

A shell-correction method is applied to nuclei far from the beta stability line and its suitability to describe effects of the particle continuum is discussed. The sensitivity of predicted locations of one- and two-particle drip lines to details of the macroscopic-microscopic model is analyzed.Comment: 22 REVTeX pages, 13 uuencoded postscript figures available upon reques

OPEN XAL Status Report 2015

MOPW1050International audienceOpen XAL is an accelerator physics software platformdeveloped in collaboration among several facilitiesaround the world. The Open XAL collaboration wasformed in 2010 to port, improve and extend the successfulXAL platform used at the Spallation Neutron Source foruse in the broader accelerator community and to establishit as the standard platform for accelerator physicssoftware. The site-independent core is complete, activeapplications have been ported, and now we are in theprocess of verification and transitioning to using OpenXAL in production. This paper will present the currentstatus and a roadmap for this project

Development and characterization of epoxy nanocomposites based on nano-structured oil palm ash.

The aim of this study is to utilize the bio-agricultural waste as filler material for composite production which are abundantly available and low cost compared to the silica, alumina etc. The lacks of sufficient scientific information about the utilization of the oil palm ash (OPA) on composites production were the driving force for the choice of this work. Furthermore, the effect of filler loading percentage on physical, mechanical, thermal and morphology properties of the epoxy nanocomposites were studied. It was concluded that the size of the OPA had been successfully reduced from macromolecular to the nano-size range by high energy ball milling and was confirmed by TEM analysis. The density of the nano-structured OPA filled epoxy composites revealed that increasing filler loading will eventually increase the density. The tensile and flexural strength attained maximum value when the filler loading was 3%. Also, increase in the thermal stability was observed in case of 3% filler loading and was attributed to the increase in cross-linking of the epoxy resin in the presence of nano-stuctured OPA and having minimum particle to particle interaction and well dispersed nanoparticles