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M. R. Whalley

Publications and source records attributed to M. R. Whalley.

10 recordsLinked to original sources

A database for quarkonium and open heavy-flavour production in hadronic collisions with HepData

We report on the creation of a database for quarkonium and open heavy-flavour production in hadronic collisions. This database, made as a collaboration between HepData and the ReteQuarkonii network of the integrating activity I3HP2 of the 7th Framework Programme, provides an up-to-date review on quarkonia and open heavy-flavour existing data. We first present the physics motivation for this project, which is connected to the aim of the ReteQuarkonii network, studies of open heavy-flavour hadrons and quarkonia in nucleus-nucleus collisions. Then we give a general overview of the database and describe the HepData database for particle physics, which is the framework of the quarkonia database. Finally we describe the functionalities of the database with as example the comparison of the production cross section for the J/$ψ$ meson at different energies.

hep-ex↗

Tevatron-for-LHC Report of the QCD Working Group

The experiments at Run 2 of the Tevatron have each accumulated over 1 inverse femtobarn of high-transverse momentum data. Such a dataset allows for the first precision (i.e. comparisons between theory and experiment at the few percent level) tests of QCD at a hadron collider. While the Large Hadron Collider has been designed as a discovery machine, basic QCD analyses will still need to be performed to understand the working environment. The Tevatron-for-LHC workshop was conceived as a communication link to pass on the expertise of the Tevatron and to test new analysis ideas coming from the LHC community. The TeV4LHC QCD Working Group focussed on important aspects of QCD at hadron colliders: jet definitions, extraction and use of Parton Distribution Functions, the underlying event, Monte Carlo tunes, and diffractive physics. This report summarizes some of the results achieved during this workshop.

hep-ph↗

HepForge: A lightweight development environment for HEP software

Setting up the infrastructure to manage a software project can become a task as significant writing the software itself. A variety of useful open source tools are available, such as Web-based viewers for version control systems, "wikis" for collaborative discussions and bug-tracking systems, but their use in high-energy physics, outside large collaborations, is insubstantial. Understandably, physicists would rather do physics than configure project management tools. We introduce the CEDAR HepForge system, which provides a lightweight development environment for HEP software. Services available as part of HepForge include the above-mentioned tools as well as mailing lists, shell accounts, archiving of releases and low-maintenance Web space. HepForge also exists to promote best-practice software development methods and to provide a central repository for re-usable HEP software and phenomenology codes.

hep-ph↗

HepData and JetWeb: HEP data archiving and model validation

The CEDAR collaboration is extending and combining the JetWeb and HepData systems to provide a single service for tuning and validating models of high-energy physics processes. The centrepiece of this activity is the fitting by JetWeb of observables computed from Monte Carlo event generator events against their experimentally determined distributions, as stored in HepData. Caching the results of the JetWeb simulation and comparison stages provides a single cumulative database of event generator tunings, fitted against a wide range of experimental quantities. An important feature of this integration is a family of XML data formats, called HepML.

hep-ph↗

The Les Houches Accord PDFs (LHAPDF) and Lhaglue

We describe the development of the LHAPDF library from its initial implementation following the Les Houches meeting in 2001 to its present state as a functional replacement for PDFLIB. Brief details are given of how to install and use the library together with the PDF sets available. We also describe LHAGLUE, an add-on PDFLIB look-a-like interface to LHAPDF, which facilitates using LHAPDF with existing Monte Carlo generators such as PYTHIA and HERWIG.

hep-ph↗

The CEDAR Project

We describe the plans and objectives of the CEDAR project (Combined e-Science Data Analysis Resource for High Energy Physics) newly funded by the PPARC e-Science programme in the UK. CEDAR will combine the strengths of the well established and widely used HEPDATA database of HEP data and the innovative JetWeb data/Monte Carlo comparison facility, built on the HZTOOL package, and will exploit developing grid technology. The current status and future plans of both of these individual sub-projects within the CEDAR framework are described, showing how they will cohesively provide (a) an extensive archive of Reaction Data, (b) validation and tuning of Monte Carlo programs against these reaction data sets, and (c) a validated code repository for a wide range of HEP code such as parton distribution functions and other calculation codes used by particle physicists. Once established it is envisaged CEDAR will become an important Grid tool used by LHC experimentalists in their analyses and may well serve as a model in other branches of science where there is a need to compare data and complex simulations.

hep-ph↗

A New Neutrino Cross Section Database

We describe a new web based data resource being developed to provide access to accurate and validated cross sections of low energy neutrino and antineutrino interactions. The proposed content of this database are outlined which cover total and differential cross from inclusive, quasi-elastic and exclusive pion production processes from charged and neutral current interactions. Efforts to obtain these data, which come mainly from old bubble chamber experiments, are described as well as the implementation of an embryonic web site to make the resource generally accessible.

hep-ph↗

Overview of the COMPETE Program

Nowadays, scientific databases have become the bread-and-butter of particle physicists. These databases must be maintained and checked repeatedly to insure the accuracy of their content. The COMPETE collaboration aims at motivating data maintenance via the interfacing of theory and experiment at the database level. The database concept then needs to be supplemented by a "model-base". Such an object enables one not only to decide what the best description may be, but also to discern what potential problems exist in the data. The systematization of such a cross-fertilization between models and data results in the "object of knowledge" that is the point at which all existing information resources on a given problem could converge. There are many advantages to such a global approach. First of all, the maintenance of a data set is not a static task: it needs to be motivated by physics. The second advantage is that one can have a common testing ground for theories and models. Thirdly, an extensive theoretical database can be used to plan new experiments and to predict various quantities. Finally, as new data come in, one can very quickly decide on their theoretical impact, and hence immediately evaluate the need for new physics ideas. As we want to treat a large amount of data and many models, computer technology constitutes an important part of our activity. We have concentrated on the elaboration of artificial intelligence decision-making algorithms, as well as on the delivery of computer tools for the end-user. Further linkage with existing databases, such as PDG, COMPAS, and HEPDATA is being developed or planned.

hep-ph↗

Total Cross Sections of e+ e- --> hadrons and pQCD Tests

In the light of recent muon (g-2) result by the E821 experiment at BNL, the importance of and interest in the total hadronic cross sections in e+ e- collisions and R(e+ e- --> hadrons) have been heightened. We report on the integrated data compilation of available data of e+ e- --> hadrons, transformed to a unique and meaningful style that implements the pure QED radiative corrections, from the PPDS and HEPDATA databases by the COMPETE Group. In particular, the continuum data sets are extracted where the direct comparison of the parton models and different variants of the pQCD corrections can be made and which will be useful for the future refinements of alpha_s(Q^2) and alpha_QED(Q^2).

hep-ph↗

A compilation of total cross section data on e^+ e^- --> hadrons and pQCD tests

All available data on the total cross sections and R-ratio of e^+ e^- --> hadrons are compiled from the PPDS(DataGuide), PPDS(ReacData) and HEPDATA(Reaction) databases and transformed to a compilation of data on the e^+ e^- --> quark antiquark --> hadrons in the continuum region which can be used in tests of the parton model and pQCD calculations. This evaluated data compilation is made available in PPDS system and is accessible through the Web. It is shown that current predictions from the parton model and pQCD are well supported by this world "continuum" data compilation which can then be used in future refinements of the alpha_s(Q^2) as well as alpha_{QED}(Q^2) evolution forms.

hep-ph↗