The mass spectra and decay properties of dimesonic states, using the Hellmann potential

Mass spectra of the dimesonic (meson-antimeson) molecular states are computed using the Hellmann potential in variational approach, which consists of relativistic correction to kinetic energy term as well as to the potential energy term. For the study of molecular bound state system, the Hellmann potential of the form $V(r)=-\frac{\alpha_{s}}{r} + \frac{B e^{-Cr}}{r}$ is being used. The one pion exchange potential (OPEP) is also incorporated in the mass calculation. The digamma decay width and decay width of the dimesonic system are evaluated using the wave function. The experimental states such as $f_{0}(980)$, $b_{1}(1235)$, $h_{1}(1380)$, $a_{0}(1450)$, $f_{0}(1500)$, $f_{2}'(1525)$,$f_{2}(1565)$, $h_{1}(1595)$, $a_{2}(1700)$, $f_{0}(1710)$, $f_{2}(1810)$ are compared with dimesonic states. Many of these states (masses and their decay properties) are close to our theoretical predictions.Comment: 11 pages, 4 table

Analysis and Design of Circular Shape Microstrip Antenna for Wireless Communication System

The circular microstrip antenna element is formed by radiating disk closely spaced above a ground plane. It is modeled as a cylindrical cavity with magnetic walls which can be resonant in the transverse magnetic modes. This circular shape microstrip antenna is analysed using cavity model and fields within the cylindrical cavity, radiation pattern and resonant frequency have been calculated. In this paper the circular microstrip antenna is designed at resonant frequency r f = 2.5 GHz. A suitable substrate of relative permittivity r = 4.2 and of thickness h = 1.6 mm is used to design the antenna. The simulation of this microstrip antenna is done on IE3D software and matlab. At last the simulation result and practical result of return loss are compared

Development of high efficiency solar cells on silicon web

Web base material is being improved with a goal toward obtaining solar cell efficiencies in excess of 18% (AM1). Carrier loss mechanisms in web silicon was investigated, techniques were developed to reduce carrier recombination in the web, and web cells were fabricated using effective surface passivation. The effect of stress on web cell performance was also investigated