Halo Structure Of C-19 Via The (p,d) Reaction

We have investigated the heaviest one-neutron halo candidate C-19 nucleus. Few-body model calculations of cross section angular distributions for the C-19(p,d)C-18 reaction, together with the test calculations carried out for the C-17(p,d)C-16 reaction, at a low incident energy are presented for different possible halo-neutron configurations. We show that there is a clear distinction between in particular $\ell_{n}=0$ and $\ell_{n}=2$ halo transfers. The sensitivity of the cross sections to the assumed C-19 single neutron separation energy is discussed.Comment: LaTEX (uses article.sty), 11 pages and 4 figures (in PS format). Please check http://physics.gantep.edu.tr/~nuclear/publications.html for other other studies of Nuclear Physics Group at University of Gaziantep. To be published in Few Body Systems Journal in May 200

A U(3)U(3) Gauge Theory on Fuzzy Extra Dimensions

In this article, we explore the low energy structure of a $U(3)$ gauge theory over spaces with fuzzy sphere(s) as extra dimensions. In particular, we determine the equivariant parametrization of the gauge fields, which transform either invariantly or as vectors under the combined action of $SU(2)$ rotations of the fuzzy spheres and those $U(3)$ gauge transformations generated by $SU(2) \subset U(3)$ carrying the spin $1$ irreducible representation of $SU(2)$. The cases of a single fuzzy sphere $S_F^2$ and a particular direct sum of concentric fuzzy spheres, $S_F^{2 \, Int}$, covering the monopole bundle sectors with windings $\pm 1$ are treated in full and the low energy degrees of freedom for the gauge fields are obtained. Employing the parametrizations of the fields in the former case, we determine a low energy action by tracing over the fuzzy sphere and show that the emerging model is abelian Higgs type with $U(1) \times U(1)$ gauge symmetry and possess vortex solutions on ${\mathbb R}^2$, which we discuss in some detail. Generalization of our formulation to the equivariant parametrization of gauge fields in $U(n)$ theories is also briefly addressed.Comment: 27+1 page

Significance Of Deuteron Breakup In A Halo Transfer Reaction

We discuss the quasi-adiabatic approximations to the three-body wavefunction in breakup processes, clarifying the assumptions underlying the model. This suggests alternative approximation schemes. Using different theoretical three-body models, calculated differential cross section angular distributions for the Be-11(p,d) reaction,for which new preliminary data have been reported at 35 MeV, are presented. We show that calculations are sensitive to the inclusion of deuteron breakup and to the breakup model used, particularly if used to deduce absolute spectroscopic information on the 0{+} and 2{+} Be-10 core state parentages. There is also considerable sensitivity to the model used in calculations of the relative cross sections to the two states.Comment: LaTEX (uses article.sty), 16 pages and 3 figures (EPS format). Please check http://physics.gantep.edu.tr/~nuclear/publications.html for other other studies of Nuclear Physics Group at University of Gaziante

Investigation of phase-equivalent potentials by a halo transfer reaction

Using the supersymmetric quantum mechanics we investigate the wave function-sensitive properties of the supersymmetric potentials which have received a lot of attention in the literature recently. We show that a superdeep potential and its phase-equivalent shallow-partner potential give very similar "rms" values for the weakly bound systems such as the deuteron and 11Be nuclei. Although the corresponding eigenstates differ in the node-number, our investigation on the 11Be(p,d)10Be single nucleon halo transfer reaction at 35 MeV show that also other physical quantities such as the cross section angular distributions calculated using these wave functions reflect the nodal structure rather weakly. This lends support to two nearly equivalent treatments of the Pauli principle.Comment: 20 pages article in LaTEX (uses standard article.sty). Figures can be obtained from author(s). Please check "http://www1.gantep.edu.tr/~ozer" for other studies of Nuclear Physics Group at University of Gaziante

Enhanced transmission of electromagnetic waves through split-ring resonator-shaped apertures

The design of aperture shape is a promising approach for enhanced transmission through a subwavelength aperture. We designed split-ring-resonator (SRR)-shaped apertures in order to increase the transmission through subwavelength apertures by making use of the strong localization of the electromagnetic field in SRR-shaped apertures. We obtained a promising result of 104-fold enhancement by utilizing SRR-shaped apertures. It is possible to use these proposed structures at optical frequencies by making several modifications such as decreasing the sharpness of edges and increasing the gap width. Since SRRs are already being realized at optical frequencies, our proposed SRR-shaped aperture structures are promising candidates for novel applications