330 research outputs found
Local-Duality QCD Sum Rules for Pseudoscalar-Meson Form Factors
We scrutinize recent findings on the charged-pion elastic form factor and the
form factors entering in neutral-meson-to-photons transition amplitudes within
the framework of QCD sum rules.Comment: 4 pages, 4 figures, contributed to "QCD@Work 2012 - International
Workshop on Quantum Chromodynamics: Theory and Experiment" (18 - 21 June
2012, Lecce, Italy), to appear in the proceeding
aDORe djatoka: An Open-Source Jpeg 2000 Image Server and Dissemination Service Framework
4th International Conference on Open RepositoriesThis presentation was part of the session : Conference PresentationsDate: 2009-05-19 03:00 PM – 04:30 PMThe JPEG 2000 image format has attracted considerable attention due to its rich feature set defined in a multi-part open ISO standard, and its potential use as a holy-grail preservation format providing both lossless compression and rich service format features. Until recently there was lack of an implementation agnostic (e.g., Kakadu, Aware, etc) API for JPEG 2000 compression and extraction, and an open-source service framework, upon which rich Web 2.0-style applications can be developed. Recently we engaged in the development of aDORe djatoka , an open-source JPEG 2000 image server and dissemination framework to help address some of these issues. The djatoka image server is geared towards Web 2.0 style reuse through URI-addressability of all image disseminations including regions, rotations, and format transformations. Djatoka also provides a JPEG 2000 compression / extraction API that serves as an abstraction layer from the underlying JPEG 2000 library (e.g., Kakadu, Aware, etc). The initial release has attracted considerable interest and is already being used in production environments, such as at the Biodiversity Heritage Library , who uses djatoka to serve more than eleven million images. This presentation introduces the aDORe djatoka image server and describes various interoperability approaches with existing repository systems. Djatoka was derived from a concrete need to introduce a solution to disseminate high-resolution images stored in an aDORe repository system. Djatoka is able to disseminate images that reside either in a repository environment or that are Web-accessible at arbitrary URIs. Since dynamic service requests pertaining to an identified resource (the entire JPEG 2000 image) are being made, the OpenURL Framework was selected to provide an extensible dissemination service framework. The OpenURL service layer simplifies development and provides exciting interoperability opportunities. The presentation will showcase the flexibility of this interface by introducing a mobile image collection viewer developed for the iPhone / iTouch platform
Pseudoscalar-Meson Form Factors: A Fresh Look by QCD Sum Rules
Confronted with some surprising claims about experimentally measured or
theoretically expected dependencies on the involved momentum transfer of
various form factors of pseudoscalar mesons, we reassess the present status of
these quantities by means of QCD sum rules. This approach provides
well-developed and very efficient tools to relate in an analytical manner the
parameters of QCD to the empirical properties of hadrons. Within this
framework, we show that a few theoretical findings for the pion elastic form
factor and one experimental result for the pion-to-photon transition form
factor are at odds with rather general fundamental considerations.Comment: 3 pages, 3 figures, contributed to "Quark Confinement and the Hadron
Spectrum X" (8 - 12 October 2012, TUM Campus Garching, Munich, Germany), to
appear in the proceeding
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