52,000 research outputs found
Realtime 3D graphics programming using the Quake3 engine
We present a lab assignment that accompanies a complete module called Real-time Graphics . The students task is to get familiar with content creation and programming a (previously) commercial 3D engine. In a first task, students have to create 3D content, which is integrated into the Quake3 engine. In a second task, the students have to implement a simple animation and finally add an impressive 3D graphics effect to the Quake3 engine. The lecture has been taught four times from 2004 to 2007. We present the assignment and report on experiences that we have gained
On timelike and spacelike hard exclusive reactions
We show to next-to-leading order accuracy in the strong coupling alpha_s how
the collinear factorization properties of QCD in the generalized Bjorken regime
relate exclusive amplitudes for spacelike and timelike hadronic processes. This
yields simple space--to--timelike relations linking the amplitudes for
electroproduction of a photon or meson to those for photo- or meso-production
of a lepton pair. These relations constitute a new test of the relevance of
leading twist analyzes of experimental data.Comment: v2: major text revision; results, references, and author added; v3:
matches the published version Phys. Rev. D86, rapid communication
Probing GPDs in photoproduction processes at hadron colliders
Generalized parton distributions (GPDs) enter QCD factorization theorems for
hard exclusive reactions. They encode rich information about hadron partonic
structure. We explore a possibility to constrain GPDs in experiments at LHC
considering two different exclusive processes: the timelike Compton scattering
and the photoproduction of heavy vector mesons.Comment: 6 pages, 2 figures; presented at PHOTON 2015: International
Conference on the Structure and the Interactions of the Photon, Novosibirsk,
Russia, 15 - 19 June, 2015. arXiv admin note: text overlap with
arXiv:1411.375
Probing GPDs in Ultraperipheral Collisions
Ultraperipheral collisions in hadron colliders give new opportunites to
investigate the hadron stucture through exclusive photoproduction processes. We
describe the possibility of measuring the Generalized Parton Distributions in
the Timelike Compton Scattering process and in the production of heavy vector
meson.Comment: to appear in Proceedings Diffraction 2014, Primosten, Croatia, sept
10-16, 201
GPDs in heavy meson production and Compton scattering
Exclusive processes of heavy meson production and spacelike and timelike
deeply virtual Compton scattering allow us to investigate the hadron structure
in terms of Generalized Parton Distributions (GPDs). We review recent
developments in the NLO description of such processes.Comment: To appear in the proceedings of the 6th International Conference on
the Physics Opportunities at an Electron-Ion Collide
Monolithically integrated active optical devices
Considerations relevant to the monolithic integration of optical detectors, lasers, and modulators with high speed amplifiers are discussed. Some design considerations for representative subsystems in the GaAs-AlGaAs and GaInAs-InP materials systems are described. Results of a detailed numerical design of an electro-optical birefringent filter for monolithic integration with a laser diode is described, and early experimental results on monolithic integration of broadband MESFET amplifiers with photoconductive detectors are reported
Defect free global minima in Thomson's problem of charges on a sphere
Given unit points charges on the surface of a unit conducting sphere,
what configuration of charges minimizes the Coulombic energy ? Due to an exponential rise in good local minima, finding global
minima for this problem, or even approaches to do so has proven extremely
difficult. For \hbox{} recent theoretical work based on
elasticity theory, and subsequent numerical work has shown, that for --1000 adding dislocation defects to a symmetric icosadeltahedral lattice
lowers the energy. Here we show that in fact this approach holds for all ,
and we give a complete or near complete catalogue of defect free global minima.Comment: Revisions in Tables and Reference
- …