NLO Scale Dependence of Semi-Inclusive Processes

We discuss the order \alpha_s^2 gluon initiated QCD corrections to one particle inclusive deep inelastic processes. We focus in the NLO evolution kernels relevant for the non homogeneous QCD scale dependence of these cross sections and factorization.Comment: Poster presentation at the XXIII Physics in Collision Conference (PIC03), Zeuthen, Germany, June 2003, 3 pages, LaTeX, 4 eps figures, PSN FRAP1

Design, analysis and test verification of advanced encapsulation systems

Analytical models were developed to perform optical, thermal, electrical and structural analyses on candidate encapsulation systems. Qualification testing, specimens of various types, and a finalized optimum design are projected

Deep inelastic scattering, diffraction, and all that

These lectures include an introduction to the partonic description of the proton, the photon and the `colour singlet', as seen in inclusive and semi-inclusive DIS, in $e^+e^-$ collisions, and in diffractive processes, respectively. Their formal treatment using structure, fragmentation, and fracture functions is outlined giving an insight into the perturbative QCD framework for these functions. Examples and comparisons with experimental data from LEP, HERA, and Tevatron are also covered.Comment: 46 pages, 52 postscript figures, LaTeX, aipproc.sty. To be published in the proceedings of VII Mexican Workshop on Particles and Field

Collapse of the Gd3+Gd^{3+} ESR fine structure throughout the coherent temperature of the Gd-doped Kondo Semiconductor CeFe4P12CeFe_{4}P_{12}

Experiments on the $Gd^{3+}$ Electron Spin Resonance (ESR) in the filled skutterudite $Ce_{1-x}Gd_{x}Fe_{4}P_{12}$ ($x \approx 0.001$), at temperatures where the host resistivity manifests a smooth insulator-metal crossover, provides evidence of the underlying Kondo physics associated with this system. At low temperatures (below $T \approx K$), $Ce_{1-x}Gd_{x}Fe_{4}P_{12}$ behaves as a Kondo-insulator with a relatively large hybridization gap, and the $Gd^{3+}$ ESR spectra displays a fine structure with lorentzian line shape, typical of insulating media. The electronic gap is attributed to the large hybridization present in the coherent regime of a Kondo lattice, when Ce 4f-electrons cooperate with band properties at half-filling. Mean-field calculations suggest that the electron-phonon interaction is fundamental at explaining the strong 4f-electron hybridization in this filled skutterudite. The resulting electronic structure is strongly temperature dependent, and at about $T^{*} \approx 160 K$ the system undergoes an insulator-to-metal transition induced by the withdrawal of 4f-electrons from the Fermi volume, the system becoming metallic and non-magnetic. The $Gd^{3+}$ ESR fine structure coalesces into a single dysonian resonance, as in metals. Still, our simulations suggest that exchange-narrowing via the usual Korringa mechanism, alone, is not capable of describing the thermal behavior of the ESR spectra in the entire temperature region ($4.2$ - $300$ K). We propose that temperature activated fluctuating-valence of the Ce ions is the missing ingredient that, added to the usual exchange-narrowing mechanism, fully describes this unique temperature dependence of the $Gd^{3+}$ ESR fine structure observed in $Ce_{1-x}Gd_{x}Fe_{4}P_{12}$.Comment: 19 pages, 6 figure