Silicon Sensor Technologies for the ATLAS IBL Upgrade

AbstractAn overview of radiation hard planar and 3D pixel sensor technologies currently under development for ATLAS upgrades is presented. T*he first upgrade will be the installation in 2013 of an additional pixel layer inside the current Detector, the Insertable B Layer (IBL). The two technologies are competing to equip the IBL. The IBL sensor qualification procedure is described. Beam test results of un-irradiated and irradiated planar and 3D sensors are presented

Fractionalization of minimal excitations in integer quantum Hall edge channels

A theoretical study of the single electron coherence properties of Lorentzian and rectangular pulses is presented. By combining bosonization and the Floquet scattering approach, the effect of interactions on a periodic source of voltage pulses is computed exactly. When such excitations are injected into one of the channels of a system of two copropagating quantum Hall edge channels, they fractionalize into pulses whose charge and shape reflects the properties of interactions. We show that the dependence of fractionalization induced electron/hole pair production in the pulses amplitude contains clear signatures of the fractionalization of the individual excitations. We propose an experimental setup combining a source of Lorentzian pulses and an Hanbury Brown and Twiss interferometer to measure interaction induced electron/hole pair production and more generally to reconstruct single electron coherence of these excitations before and after their fractionalization.Comment: 18 pages, 10 figures, 1 tabl

The Early Financing of the Consolidated Association of the Planters of Louisiana

The Louisiana State University is now in possession of valuable records of the defunct Consolidated Association of the Planters of Louisiana”: a bank which was established over a century ago. Although this Institution played an important role in the economic development of Louisiana, relatively little is known about it today. Taking the available records as a source of information, the present study describes and analyzes the organization and the operation of this now type of banking. Particular emphasis is placed upon the fact that the institution was financed through the sale of bonds guaranteed by the State; and for that reason most of the study is centered about the negotiations with Baring Brothers and Company of London. The manuscripts of the Consolidated Association reveal much added information on a particular phase of Louisiana’s attempts to entice outside capital far the betterment of the State and its people. Therefore, the important manuscripts referring to the first ten years of the Bank’s history have been presented in full, either in the body of the thesis or in the appendix, and in the translated form. No attempt was made to completely analyze and compile all the information available on this bank, but the thesis is an introduction which will permit a further study in the affairs of the Consolidated Association and of the effects it had on the economic and banking development of Louisiana

Raman scattering through surfaces having biaxial symmetry

Magnetic Raman scattering in two-leg spin ladder materials and the relationship between the anisotropic exchange integrals are analyzed by P. J. Freitas and R. R. P. Singh in Phys. Rev. B, {\bf 62}, 14113 (2000). The angular dependence of the two-magnon scattering is shown to provide information for the magnetic anisotropy in the Sr_14Cu_24O_41 and La_6Ca_8Cu_24O_41 compounds. We point out that the experimental results of polarized Raman measurements at arbitrary angles with respect to the crystal axes have to be corrected for the light ellipticity induced inside the optically anisotropic crystals. We refer quantitatively to the case of Sr_14Cu_24O_41 and discuss potential implications for spectroscopic studies in other materials with strong anisotropy.Comment: To be published as a Comment in Phys. Rev.