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Data Preservation and Long Term Analysis in High Energy Physics
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 22/06/2012
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...
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Proceedings of the 2009 CERN-Latin-American School of High-Energy Physics, Recinto Quirama, Colombia, 15 - 28 March 2009
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 28/10/2010
Relevância na Pesquisa
963.83586%
The CERN-Latin-American 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 lectures on quantum
field theory, quantum chromodynamics, physics beyond the Standard Model,
neutrino physics, flavour physics and CP violation, particle cosmology,
high-energy astro-particle physics, and heavy-ion physics, as well as trigger
and data acquisition, and commissioning and early physics analysis of the ATLAS
and CMS experiments. Also included are write-ups of short review projects
performed by the student discussions groups.; Comment: 10 lectures, 560 pages, published as CERN Yellow Report
http://cdsweb.cern.ch/record/1119305
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Computing trends using graphic processor in high energy physics
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 30/06/2011
Relevância na Pesquisa
963.0013%
#Computer Science - Distributed, Parallel, and Cluster Computing#High Energy Physics - Experiment#Physics - Computational Physics
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.
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Silicon detectors for the next generation of high energy physics experiments: expected degradation
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 31/12/2005
Relevância na Pesquisa
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There exists an enormous interest for the study of very high energy domain in
particle physics, both theoretically and experimentally, in the aim to
construct a general theory of the fundamental constituents of matter and of
their interactions. Until now, semiconductor detectors have widely been used in
modern high energy physics experiments. They are elements of the high
resolution vertex and tracking system, as well as of calorimeters. The main
motivation of this work is to discuss how to prepare some possible detectors -
only silicon option being considered, for the new era of HEP challenges because
the bulk displacement damage in the detector, consequence of irradiation,
produces effects at the device level that limit their long time utilisation,
increasing the leakage current and the depletion voltage, eventually up to
breakdown, and thus affecting the lifetime of detector systems. In this paper,
physical phenomena that conduce to the degradation of the detector are
discussed and effects are analysed at the device level (leakage current and
effective carrier concentration) in the radiation environments expected in the
next generation of hadron colliders after LHC, at the next lepton and
gamma-gamma colliders, as well as in astroparticle experiments...
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Indian Contributions to High Energy Physics in the 20th Century
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 07/02/2006
Relevância na Pesquisa
964.6259%
#Physics - History and Philosophy of Physics#High Energy Physics - Phenomenology#High Energy Physics - Theory
The inward bound path of discovery unravelling the mysteries of matter and
the forces that hold it together has culminated at the end of the twentieth
century in a theory of the Fundamental Forces of Nature based on Nonabelian
Gauge Fields, called the Standard Model of High Energy Physics. In this article
we trace the historical development of the ideas and the experimental
discoveries on which this theory is based. We also mark significant Indian
contributions wherever possible. Finally we have a glimpse at future
developments. An Appendix on more Indian contributions is added at the end.; Comment: 15 pages. Invited talk presented at the XIV DAE Symposium on High
Energy Physics, Univ. of Hyderabad, Dec. 2000
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Integrated Circuit Design in US High-Energy Physics
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
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.
Link permanente para citações:
Testing the Bell Inequality at Experiments of High Energy Physics
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 07/04/2009
Relevância na Pesquisa
963.3091%
Besides using the laser beam, it is very tempting to directly testify the
Bell inequality at high energy experiments where the spin correlation is
exactly what the original Bell inequality investigates. In this work, we follow
the proposal raised in literature and use the successive decays
$J/\psi\to\gamma\eta_c\to \Lambda\bar\Lambda\to p\pi^-\bar p\pi^+$ to testify
the Bell inequality. Our goal is twofold, namely, we first make a Monte-Carlo
simulation of the processes based on the quantum field theory (QFT). Since the
underlying theory is QFT, it implies that we pre-admit the validity of quantum
picture. Even though the QFT is true, we need to find how big the database
should be, so that we can clearly show deviations of the correlation from the
Bell inequality determined by the local hidden variable theory. There have been
some critiques on the proposed method, so in the second part, we suggest some
improvements which may help to remedy the ambiguities indicated by the
critiques. It may be realized at an updated facility of high energy physics,
such as BES III.; Comment: 16 pages, 5 figures
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Non-relativistic high-energy physics: top production and dark matter annihilation
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 26/06/2015
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...
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Quantitative Analysis of the Publishing Landscape in High-Energy Physics
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 26/11/2006
Relevância na Pesquisa
963.3091%
#Computer Science - Digital Libraries#High Energy Physics - Experiment#High Energy Physics - Phenomenology#High Energy Physics - Theory
World-wide collaboration in high-energy physics (HEP) is a tradition which
dates back several decades, with scientific publications mostly coauthored by
scientists from different countries. This coauthorship phenomenon makes it
difficult to identify precisely the ``share'' of each country in HEP scientific
production. One year's worth of HEP scientific articles published in
peer-reviewed journals is analysed and their authors are uniquely assigned to
countries. This method allows the first correct estimation on a ``pro rata''
basis of the share of HEP scientific publishing among several countries and
institutions. The results provide an interesting insight into the geographical
collaborative patterns of the HEP community. The HEP publishing landscape is
further analysed to provide information on the journals favoured by the HEP
community and on the geographical variation of their author bases. These
results provide quantitative input to the ongoing debate on the possible
transition of HEP publishing to an Open Access model.; Comment: For a better on-screen viewing experience this paper can also be
obtained at:
http://doc.cern.ch/archive/electronic/cern/preprints/open/open-2006-065.pdf
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A Thousand Invisible Cords Binding Astronomy and High-Energy Physics
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 09/08/2007
Relevância na Pesquisa
969.2482%
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...
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Topics in statistical data analysis for high-energy physics
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 16/12/2010
Relevância na Pesquisa
964.059%
#Physics - Data Analysis, Statistics and Probability#High Energy Physics - Experiment#High Energy Physics - Phenomenology
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
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Quarkonium at the Frontiers of High Energy Physics: A Snowmass White Paper
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
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...
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Proceedings of the 1st Asia-Europe-Pacific School of High-Energy Physics (AEPSHEP 12), Fukuoka, Japan, 14 - 27 Oct 2012
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 07/07/2014
Relevância na Pesquisa
963.83586%
The Asia-Europe-Pacific 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 lectures on quantum
field theory, quantum chromodynamics, flavour physics and CP-violation, physics
beyond the Standard Model, neutrino physics, particle cosmology, heavy-ion
physics, as well as a presentation of recent results from the Large Hadron
Collider (LHC), practical statistics for particle physicists and a short
introduction to the principles of particle physics instrumentation.; Comment: 8 lectures, 285 pages, published as CERN Yellow Report
https://cds.cern.ch/record/1443909
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Probing High-Energy Physics with High-Precision QED Measurements
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 05/03/2002
Relevância na Pesquisa
965.4194%
#High Energy Physics - Phenomenology#Astrophysics#High Energy Physics - Experiment#High Energy Physics - Theory
I summarize our self-contained determinations of the lowest order hadronic
contributions to the anomalous magnetic moments a_{\mu,\tau} of the muon and
tau leptons, the running QED coupling \alpha(M_Z) and the muonium hyperfine
splitting \nu. Using as a revised estimate of the light-by light scattering:
a_\mu(LL)=85(18) 10^{-11}, we deduce: a_\mu^{SM} = 116 591 861(78) 10^{-11},
a_\tau^{SM} = 117 759(7) 10^{-8}, giving: a_\mu^{SM}-a_\mu^{exp}=162(170)
10^{-11}. We also obtain: \alpha^{-1}(M_Z)=128.926(25) and the Fermi energy
splitting: \nu_F^{SM}=4 459 031 783(229) {Hz}. Lower bounds on some eventual
new physics are given, while \nu_F^{SM} leads e.g. to m_\mu/m_e=206.768 276(11)
in remarkable agreement with the data.; Comment: Latex 2e, 11 pages, 4 Tables, 1 eps.figure. Talk presented at the 1st
High-Energy Physics Madagascar International Conference Series (HEP-MAD'01)
27th sept-5th oct. 2001, Antananarivo
Link permanente para citações:
A New Era in High-energy Physics
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 15/05/2002
Relevância na Pesquisa
963.6121%
#High Energy Physics - Phenomenology#Astrophysics#General Relativity and Quantum Cosmology#High Energy Physics - Theory
In TeV-scale gravity, scattering of particles with center-of-mass energy of
the order of a few TeV can lead to the creation of nonperturbative, extended,
higher-dimensional gravitational objects: Branes. Neutral or charged, spinning
or spinless, Einsteinian or supersymmetric, low-energy branes could
dramatically change our picture of high-energy physics. Will we create branes
in future particle colliders, observe them from ultra high energy cosmic rays,
and discover them to be dark matter?; Comment: 8 pages, 2 figures. Essay submitted on Mar 26, 2002 to the Gravity
Research Foundation. Awarded the third prize in the 2002 GRF competition
Link permanente para citações:
Data Preservation and Long Term Analysis in High Energy Physics
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 09/07/2009
Relevância na Pesquisa
964.6259%
#High Energy Physics - Experiment#Computer Science - Digital Libraries#Physics - Data Analysis, Statistics and Probability
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
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Evolutionary Computation in High Energy Physics
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 02/04/2008
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)
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A pedagogical introduction to quantum integrability, with a view towards theoretical high-energy physics
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
962.74234%
#Mathematical Physics#High Energy Physics - Theory#Nonlinear Sciences - Exactly Solvable and Integrable Systems
These are lecture notes of an introduction to quantum integrability given at
the Tenth Modave Summer School in Mathematical Physics, 2014, aimed at PhD
candidates and junior researchers in theoretical physics.
We introduce spin chains and discuss the coordinate Bethe ansatz (CBA) for a
representative example: the Heisenberg XXZ model. The focus lies on the
structure of the CBA and on its main results, deferring a detailed treatment of
the CBA for the general $M$-particle sector of the XXZ model to an appendix.
Subsequently the transfer-matrix method is discussed for the six-vertex model,
uncovering a relation between that model and the XXZ spin chain. Equipped with
this background the quantum inverse-scattering method (QISM) and algebraic
Bethe ansatz (ABA) are treated. We emphasize the use of graphical notation for
algebraic quantities as well as computations.
Finally we turn to quantum integrability in the context of theoretical
high-energy physics. We discuss factorized scattering in two-dimensional QFT,
and conclude with a qualitative introduction to one current research topic
relating quantum integrability to theoretical high-energy physics: the
Bethe/gauge correspondence.; Comment: 74 pages, 10 figures, 3 tables; v2: minor corrections
Link permanente para citações:
Data Preservation in High Energy Physics
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 11/11/2011
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
Link permanente para citações:
The DPHEP Study Group: Data Preservation in High Energy Physics
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 14/02/2013
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
Link permanente para citações: