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Status Report of the DPHEP Study Group: Towards a Global Effort for Sustainable Data Preservation in High Energy Physics

Akopov, Z.; Amerio, Silvia; Asner, David; Avetisyan, Eduard; Barring, Olof; Beacham, James; Bellis, Matthew; Bernardi, Gregorio; Bethke, Siegfried; Boehnlein, Amber; Brooks, Travis; Browder, Thomas; Brun, Rene; Cartaro, Concetta; Cattaneo, Marco; Chen, Ga
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 21/05/2012 Português
Relevância na Pesquisa
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Data from high-energy physics (HEP) experiments are collected with significant financial and human effort and are mostly unique. An inter-experimental study group on HEP data preservation and long-term analysis was convened as a panel of the International Committee for Future Accelerators (ICFA). The group was formed by large collider-based experiments and investigated the technical and organisational aspects of HEP data preservation. An intermediate report was released in November 2009 addressing the general issues of data preservation in HEP. This paper includes and extends the intermediate report. It provides an analysis of the research case for data preservation and a detailed description of the various projects at experiment, laboratory and international levels. In addition, the paper provides a concrete proposal for an international organisation in charge of the data management and policies in high-energy physics.

Data Preservation in High Energy Physics

South, David M.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 17/01/2011 Português
Relevância na Pesquisa
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Data from high-energy physics (HEP) experiments are collected with significant financial and human effort and are in many cases unique. At the same time, HEP has no coherent strategy for data preservation and re-use, and many important and complex data sets are simply lost. In a period of a few years, several important and unique experimental programs will come to an end, including those at HERA, the b-factories and at the Tevatron. An inter-experimental study group on HEP data preservation and long-term analysis (DPHEP) was formed and a series of workshops were held to investigate this issue in a systematic way. The physics case for data preservation and the preservation models established by the group are presented, as well as a description of the transverse global projects and strategies already in place.; Comment: Proceedings of plenary talk given at the 18th International Conference on Computing in High Energy and Nuclear Physics (CHEP 2010). 10 pages, 9 figures

Data Preservation and Long Term Analysis in High Energy Physics

South, David M.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 22/06/2012 Português
Relevância na Pesquisa
967.4587%
Several important and unique experimental high-energy physics programmes at a variety of facilities are coming to an end, including those at HERA, the B-factories and the Tevatron. The wealth of physics data from these experiments is the result of a significant financial and human effort, and yet until recently no coherent strategy existed for data preservation and re-use. To address this issue, an inter-experimental study group on data preservation and long-term analysis in high-energy physics was convened at the end of 2008, publishing an interim report in 2009. The membership of the study group has since expanded, including the addition of the LHC experiments, and a full status report has now been released. This report greatly expands on the ideas contained in the original publication and provides a more solid set of recommendations, not only concerning data preservation and its implementation in high-energy physics, but also the future direction and organisational model of the study group. The main messages of the status report were presented for the first time at the 2012 International Conference on Computing in High Energy and Nuclear Physics and are summarised in these proceedings.; Comment: Proceedings of plenary talk given at the 2012 International Conference on Computing in High Energy and Nuclear Physics (CHEP 2012). 8 pages...

FPGA based High Speed Data Acquisition System for High Energy Physics Application

Mandal, Swagata; Sau, Suman; Chakrabarti, Amlan; Chattopadhyay, Subhasis
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 30/03/2015 Português
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In high energy physics experiments (HEP), high speed and fault resilient data communication is needed between detectors/sensors and the host PC. Transient faults can occur in the communication hardware due to various external effects like presence of charged particles, noise in the environment or radiation effects in HEP experiments and that leads to single/multiple bit error. In order to keep the communication system functional in such a radiation environment where direct intervention of human is not possible, a high speed data acquisition (DAQ) architecture is necessary which supports error recovery. This design presents an efficient implementation of field programmable gate array (FPGA) based high speed DAQ system with optical communication link supported by multi-bit error correcting model. The design has been implemented on Xilinx Kintex-7 board and is tested for board to board communication as well as for PC communication using PCI (Peripheral Component Interconnect express). Data communication speed up to 4.8 Gbps has been achieved in board to board and board to PC communication and estimation of resource utilization and critical path delay are also measured.

Correlation between radiation processes in silicon and long-time degradation of detectors for high energy physics experiments

Lazanu, Sorina; Lazanu, Ionel
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 20/11/2006 Português
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960.2061%
In this contribution, the correlation between fundamental interaction processes induced by radiation in silicon and observable effects which limit the use of silicon detectors in high energy physics experiments is investigated in the frame of a phenomenological model which includes: generation of primary defects at irradiation starting from elementary interactions in silicon; kinetics of defects, effects at the p-n junction detector level. The effects due to irradiating particles (pions, protons, neutrons), to their flux, to the anisotropy of the threshold energy in silicon, to the impurity concentrations and resistivity of the starting material are investigated as time, fluence and temperature dependences of detector characteristics. The expected degradation of the electrical parameters of detectors in the complex hadron background fields at LHC & SLHC are predicted.; Comment: prepared for the 10th International Symposium on Radiation Physics, 17-22 September, 2006, Coimbra, Portugal

Computing trends using graphic processor in high energy physics

Niculescu, Mihai; Zgura, Sorin-Ion
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 30/06/2011 Português
Relevância na Pesquisa
963.0013%
One of the main challenges in Heavy Energy Physics is to make fast analysis of high amount of experimental and simulated data. At LHC-CERN one p-p event is approximate 1 Mb in size. The time taken to analyze the data and obtain fast results depends on high computational power. The main advantage of using GPU(Graphic Processor Unit) programming over traditional CPU one is that graphical cards bring a lot of computing power at a very low price. Today a huge number of application(scientific, financial etc) began to be ported or developed for GPU, including Monte Carlo tools or data analysis tools for High Energy Physics. In this paper, we'll present current status and trends in HEP using GPU.

Integrated Circuit Design in US High-Energy Physics

De Geronimo, G.; Christian, D.; Bebek, C.; Garcia-Sciveres, M.; Von der Lippe, H.; Haller, G.; Grillo, A. A.; Newcomer, M.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
962.48305%
This whitepaper summarizes the status, plans, and challenges in the area of integrated circuit design in the United States for future High Energy Physics (HEP) experiments. It has been submitted to CPAD (Coordinating Panel for Advanced Detectors) and the HEP Community Summer Study 2013(Snowmass on the Mississippi) held in Minnesota July 29 to August 6, 2013. A workshop titled: US Workshop on IC Design for High Energy Physics, HEPIC2013 was held May 30 to June 1, 2013 at Lawrence Berkeley National Laboratory (LBNL). A draft of the whitepaper was distributed to the attendees before the workshop, the content was discussed at the meeting, and this document is the resulting final product. The scope of the whitepaper includes the following topics: Needs for IC technologies to enable future experiments in the three HEP frontiers Energy, Cosmic and Intensity Frontiers; Challenges in the different technology and circuit design areas and the related R&D needs; Motivation for using different fabrication technologies; Outlook of future technologies including 2.5D and 3D; Survey of ICs used in current experiments and ICs targeted for approved or proposed experiments; IC design at US institutes and recommendations for collaboration in the future.

Proceedings of the 2012 European School of High-Energy Physics (ESHEP 2012), La Pommeraye, Anjou, France, 06-19 Jun 2012

Grojean, C.; Mulders, M.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 28/04/2015 Português
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959.9618%
The European School of High-Energy Physics is intended to give young physicists an introduction to the theoretical aspects of recent advances in elementary particle physics. These proceedings contain lecture notes on the Standard Model of electroweak interactions, quantum chromodynamics, flavour physics, physics beyond the Standard Model, neutrino physics, and cosmology.; Comment: 8 lectures, 296 pages, published as CERN Yellow Report https://cds.cern.ch/record/1406310

Non-relativistic high-energy physics: top production and dark matter annihilation

Beneke, Martin; Steinhauser, Matthias
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 26/06/2015 Português
Relevância na Pesquisa
962.48305%
Non-relativistic physics is often associated with atomic physics and low-energy phenomena of the strong interactions between nuclei and quarks. In this review we cover three topics in contemporary high-energy physics at or close to the TeV scale, where non-relativistic dynamics plays an important if not defining role. We first discuss in detail the third-order corrections to top-quark pair production in electron-positron collisions in the threshold region, which plays a major role at a future high-energy e+ e- collider. Threshold effects are also relevant in the production of heavy particles in hadronic collisions, where in addition to the Coulomb force soft gluon radiation contributes to enhanced quantum corrections. We review the joint resummation of non-relativistic and soft gluon effects for pair production of top quarks and supersymmetric particles to next-to-next-to-leading logarithmic accuracy. The third topic deals with pair annihilation of dark matter particles within the framework of the Minimal Supersymmetric Standard Model. Here the electroweak Yukawa force generated by the exchange of gauge and Higgs bosons can cause large "Sommerfeld" enhancements of the annihilation cross section in some parameter regions.; Comment: 36 pages...

HEPMath 1.4: A Mathematica Package for Semi-Automatic Computations in High Energy Physics

Wiebusch, Martin
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
960.3871%
This article introduces the Mathematica package \emph{HEPMath} which provides a number of utilities and algorithms for High Energy Physics computations in Mathematica. Its functionality is similar to packages like FormCalc or FeynCalc, but it takes a more complete and extensible approach to implementing common High Energy Physics notations in the Mathematica language, in particular those related to tensors and index contractions. It also provides a more flexible method for the generation of numerical code which is based on new features for C code generation in Mathematica. In particular it can automatically generate Python extension modules which make the compiled functions callable from Python, thus eliminating the need to write any code in a low-level language like C or Fortran. It also contains seamless interfaces to LHAPDF, FeynArts, and LoopTools.

A Thousand Invisible Cords Binding Astronomy and High-Energy Physics

Kolb, Rocky
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 09/08/2007 Português
Relevância na Pesquisa
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The traditional realm of astronomy is the observation and study of the largest objects in the Universe, while the traditional domain of high-energy physics is the study of the smallest things in nature. But these two sciences concerned with opposite ends of the size spectrum are, in Muir's words, bound fast by a thousand invisible cords that cannot be broken. In this essay I propose that collaborations of astronomers and high-energy physicists on common problems are beneficial for both fields, and that both astronomy and high-energy physics can advance by this close and still growing relationship. Dark matter and dark energy are two of the binding cords I will use to illustrate how collaborations of astronomers and high-energy physicists on large astronomical projects can be good for astronomy, and how discoveries in astronomy can guide high-energy physicists in their quest for understanding nature on the smallest scales. Of course, the fields have some different intellectual and collaborative traditions, neither of which is ideal. The cultures of the different fields cannot be judged to be right or wrong; they either work or they don't. When astronomers and high-energy physicists work together, the binding cords can either encourage or choke creativity. The challenge facing the astronomy and high-energy physics communities is to adopt the best traditions of both fields. It is up to us to choose wisely.; Comment: Why "Fundamentalist" Physics Is Good for Astronomy (in response to the paper of Simon White...

How good are your fits? Unbinned multivariate goodness-of-fit tests in high energy physics

Williams, Mike
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
961.4255%
Multivariate analyses play an important role in high energy physics. Such analyses often involve performing an unbinned maximum likelihood fit of a probability density function (p.d.f.) to the data. This paper explores a variety of unbinned methods for determining the goodness of fit of the p.d.f. to the data. The application and performance of each method is discussed in the context of a real-life high energy physics analysis (a Dalitz-plot analysis). Several of the methods presented in this paper can also be used for the non-parametric determination of whether two samples originate from the same parent p.d.f. This can be used, e.g., to determine the quality of a detector Monte Carlo simulation without the need for a parametric expression of the efficiency.; Comment: 32 pages, 12 figures

Topics in statistical data analysis for high-energy physics

Cowan, G.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 16/12/2010 Português
Relevância na Pesquisa
964.059%
These lectures concern two topics that are becoming increasingly important in the analysis of High Energy Physics (HEP) data: Bayesian statistics and multivariate methods. In the Bayesian approach we extend the interpretation of probability to cover not only the frequency of repeatable outcomes but also to include a degree of belief. In this way we are able to associate probability with a hypothesis and thus to answer directly questions that cannot be addressed easily with traditional frequentist methods. In multivariate analysis we try to exploit as much information as possible from the characteristics that we measure for each event to distinguish between event types. In particular we will look at a method that has gained popularity in HEP in recent years: the boosted decision tree (BDT).; Comment: 22 pages, Lectures given at the 2009 European School of High-Energy Physics, Bautzen, Germany, 14-27 Jun 2009

Advanced Analysis Methods in High Energy Physics

Bhat, Pushpalatha C.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 28/06/2001 Português
Relevância na Pesquisa
959.9618%
During the coming decade, high energy physics experiments at the Fermilab Tevatron and around the globe will use very sophisticated equipment to record unprecedented amounts of data in the hope of making major discoveries that may unravel some of Nature's deepest mysteries. The discovery of the Higgs boson and signals of new physics may be around the corner. The use of advanced analysis techniques will be crucial in achieving these goals. I will discuss some of the novel methods of analysis that could prove to be particularly valuable for finding evidence of any new physics, for improving precision measurements and for exploring parameter spaces of theoretical models.; Comment: 9 pages, 5 figures, To be published in the Proceedings of the VII International Workshop on Advanced Computing and Analysis Techniques in Physics Research, Fermilab, Oct. 16-20, 2000 (American Institute of Physics, NY, 2001) edited by P.C. Bhat and M. Kasemann

Quarkonium at the Frontiers of High Energy Physics: A Snowmass White Paper

Bodwin, Geoffrey T.; Braaten, Eric; Eichten, Estia; Olsen, Stephen Lars; Pedlar, Todd K.; Russ, James
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
962.48305%
In this Snowmass White Paper, we discuss physics opportunities involving heavy quarkonia at the intensity and energy frontiers of high energy physics. We focus primarily on two specific aspects of quarkonium physics for which significant advances can be expected from experiments at both frontiers. The first aspect is the spectroscopy of charmonium and bottomonium states above the open-heavy-flavor thresholds. Experiments at e^+ e^- colliders and at hadron colliders have discovered many new, unexpected quarkonium states in the last 10 years. Many of these states are surprisingly narrow, and some have electric charge. The observations of these charged quarkonium states are the first definitive discoveries of manifestly exotic hadrons. These results challenge our understanding of the QCD spectrum. The second aspect is the production of heavy quarkonium states with large transverse momentum. Experiments at the LHC are measuring quarkonium production with high statistics at unprecedented values of p_T. Recent theoretical developments may provide a rigorous theoretical framework for inclusive production of quarkonia at large p_T. Experiments at the energy frontier will provide definitive tests of this framework. Experiments at the intensity frontier also provide an opportunity to understand the exclusive production of quarkonium states.; Comment: 43 pages...

Reference priors for high energy physics

Demortier, Luc; Jain, Supriya; Prosper, Harrison B.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
961.4255%
Bayesian inferences in high energy physics often use uniform prior distributions for parameters about which little or no information is available before data are collected. The resulting posterior distributions are therefore sensitive to the choice of parametrization for the problem and may even be improper if this choice is not carefully considered. Here we describe an extensively tested methodology, known as reference analysis, which allows one to construct parametrization-invariant priors that embody the notion of minimal informativeness in a mathematically well-defined sense. We apply this methodology to general cross section measurements and show that it yields sensible results. A recent measurement of the single top quark cross section illustrates the relevant techniques in a realistic situation.

Data Preservation and Long Term Analysis in High Energy Physics

South, David M.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 09/07/2009 Português
Relevância na Pesquisa
964.6259%
High energy physics data is a long term investment and contains the potential for physics results beyond the lifetime of a collaboration. Many existing experiments are concluding their physics programs, and looking at ways to preserve their data heritage. Preservation of high-energy physics data and data analysis structures is a challenge, and past experience has shown it can be difficult if adequate planning and resources are not provided. A study group has been formed to provide guidelines for such data preservation efforts in the future. Key areas to be investigated were identified at a workshop at DESY in January 2009, to be followed by a workshop at SLAC in May 2009. More information can be found at http://dphep.org; Comment: To appear in the proceedings of 44th Rencontres de Moriond on QCD and High Energy Interactions, La Thuile, Valle d'Aosta, Italy, 14-21 Mar 2009. 4 pages, 2 figures + 1 photo, 1 style file

Evolutionary Computation in High Energy Physics

Teodorescu, Liliana
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 02/04/2008 Português
Relevância na Pesquisa
964.059%
Evolutionary Computation is a branch of computer science with which, traditionally, High Energy Physics has fewer connections. Its methods were investigated in this field, mainly for data analysis tasks. These methods and studies are, however, less known in the high energy physics community and this motivated us to prepare this lecture. The lecture presents a general overview of the main types of algorithms based on Evolutionary Computation, as well as a review of their applications in High Energy Physics.; Comment: Lecture presented at 2006 Inverted CERN School of Computing; to be published in the school proceedings (CERN Yellow Report)

Data Preservation in High Energy Physics

Kogler, Roman; South, David M.; Steder, Michael
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 11/11/2011 Português
Relevância na Pesquisa
964.059%
Data from high-energy physics experiments are collected with significant financial and human effort and are mostly unique. However, until recently no coherent strategy existed for data preservation and re-use, and many important and complex data sets have simply been lost. While the current focus is on the LHC at CERN, in the current period several important and unique experimental programs at other facilities are coming to an end, including those at HERA, b-factories and the Tevatron. To address this issue, an inter-experimental study group on HEP data preservation and long-term analysis (DPHEP) was convened at the end of 2008. The group now aims to publish a full and detailed review of the present status of data preservation in high energy physics. This contribution summarises the results of the DPHEP study group, describing the challenges of data preservation in high energy physics and the group's first conclusions and recommendations. The physics motivation for data preservation, generic computing and preservation models, technological expectations and governance aspects at local and international levels are examined.; Comment: 8 pages, 6 figures, proceedings of ACAT 2011 poster

The DPHEP Study Group: Data Preservation in High Energy Physics

South, David M.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 14/02/2013 Português
Relevância na Pesquisa
963.3091%
An inter-experimental study group, DPHEP, was formed in 2009 to systematically investigate the technical and organisational aspects of data preservation and long-term analysis in high-energy physics, a subject which had hitherto lacked clarity in the field. The study group includes representation from all major high-energy physics collider-based experiments and laboratories, as well as computing centres and funding agencies. A major report was released in May 2012, greatly expanding on the ideas contained in a preliminary publication three years earlier, and providing a more solid set of recommendations, not only concerning data preservation and its implementation in high-energy physics, but also the future direction and organisational model of the study group. A brief description of the DPHEP Study Group and some of the key messages from the major report are presented.; Comment: 6 pages, 2 figures; proceedings of talk given at ICHEP 2012, Melbourne, July 2012