Unitary representations of the fundamental group of orbifolds

Let X be a smooth complex projective variety of dimension n and \(\mathcal {L}\) an ample line bundle on it. There is a well known bijective correspondence between the isomorphism classes of polystable vector bundles E on X with \(c_{1}(E) = 0 = c_{2} (E) \cdot c_{1} (\mathcal {L})^{n-2}\) and the equivalence classes of unitary representations of π₁(X). We show that this bijective correspondence extends to smooth orbifolds.     

Improved Design of 8-Channel Silicon-on-Insulator (SOI) Arrayed Waveguide Grating (AWG) Multiplexer Using Tapered Entry into the Slab Waveguides

An improved design of silicon-on-insulator based 8 × 8 AWG multiplexer is presented using tapered entry into the slab waveguide. Our simulation result clearly shows significant enhancement of electric field from 0.44 V/m to 0.732 V/m, reduction in insertion loss from 7.13 db to 2.7 db, with bandwidth of 230 GHz and channel spacing 200 GHz while keeping other parameters within acceptable limits.     

STUDY OF HEAVY ION MODIFIED CR-39 (DIETHYLENEGLYCOL BISALLYL CARBONATE)

The commercially available solid state nuclear track detector CR-39 was bombarded with 100 MeV Si⁸⁺ ions. The Fourier transfonned infrared (FTIR) spectroscopic technique was employed for studying the changes in chemical properties whereas differential scanning calorimetry was used for studying the changes in thermal properties. It was observed that there were substantial chemical modifications in the sample, such as the breaking of C-0 single bonds and the formation of phenolic 0-H bonds. lt was further observed that CR-39 is amorphous and rigid and shows no glass transition temperature.     

Design of a superconducting low beta niobium resonator

The proposed high current injector for the superconducting Linac at the Inter-University Accelerator Centre will have several accelerating structures, including a superconducting module which will contain low beta niobium resonators. A prototype resonator for the low beta module has been designed. The resonator has been carefully modelled to optimize the electromagnetic parameters. In order to validate them, a room-temperature copper model has been built and tested. In this paper we present details of the electromagnetic design of the low beta resonator, briefly discuss the mechanical and engineering design, and present results from the measurements on the room-temperature copper model.     

Synchronization of indirectly coupled Lorenz oscillators: An experimental study

The dynamics of indirectly coupled Lorenz circuits is investigated experimentally. The in-phase and anti-phase synchronization of indirectly coupled chaotic oscillators reported in Phys. Rev. E 81, 046216 (2010) is verified by physical experiments with electronic circuits. Two chaotic systems coupled through a common dynamic environment shows the verity of synchronization behaviours such as anti-phase synchronization, in-phase synchronization, identical synchronization, anti-synchronization, etc.