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Status Report of the DPHEP Study Group: Towards a Global Effort for Sustainable Data Preservation in High Energy Physics
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 21/05/2012
Português
Relevância na Pesquisa
960.3871%
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.
Link permanente para citações:
Heisenberg's Uncertainty Relation and Bell Inequalities in High Energy Physics
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 24/01/2011
Português
Relevância na Pesquisa
961.4255%
An effective formalism is developed to handle decaying two-state systems.
Herewith, observables of such systems can be described by a single operator in
the Heisenberg picture. This allows for using the usual framework in quantum
information theory and, hence, to enlighten the quantum feature of such systems
compared to non-decaying systems. We apply it to systems in high energy
physics, i.e. to oscillating meson-antimeson systems. In particular, we discuss
the entropic Heisenberg uncertainty relation for observables measured at
different times at accelerator facilities including the effect of CP violation,
i.e. the imbalance of matter and antimatter. An operator-form of Bell
inequalities for systems in high energy physics is presented, i.e. a
Bell-witness operator, which allows for simple analysis of unstable systems.; Comment: 17 pages
Link permanente para citações:
Nonextensive statistical mechanics - Applications to nuclear and high energy physics
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 27/01/2003
Português
Relevância na Pesquisa
958.69266%
A variety of phenomena in nuclear and high energy physics seemingly do not
satisfy the basic hypothesis for possible stationary states to be of the type
covered by Boltzmann-Gibbs (BG) statistical mechanics. More specifically, the
system appears to relax, along time, on macroscopic states which violate the
ergodic assumption. Some of these phenomena appear to follow, instead, the
prescriptions of nonextensive statistical mechanics. In the same manner that
the BG formalism is based on the entropy $S_{BG}=-k \sum_i p_i \ln p_i$, the
nonextensive one is based on the form $S_q=k(1-\sum_ip_i^q)/(q-1)$ (with
$S_1=S_{BG}$). Typically, the systems following the rules derived from the
former exhibit an {\it exponential} relaxation with time toward a stationary
state characterized by an {\it exponential} dependence on the energy ({\it
thermal equilibrium}), whereas those following the rules derived from the
latter are characterized by (asymptotic) {\it power-laws} (both the typical
time dependences, and the energy distribution at the stationary state). A brief
review of this theory is given here, as well as of some of its applications,
such as electron-positron annihilation producing hadronic jets, collisions
involving heavy nuclei, the solar neutrino problem...
Link permanente para citações:
Data Preservation in High Energy Physics
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 17/01/2011
Português
Relevância na Pesquisa
962.1753%
#High Energy Physics - Experiment#Computer Science - Digital Libraries#Physics - Data Analysis, Statistics and Probability
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
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 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...
Link permanente para citações:
Emerging Computing Technologies in High Energy Physics
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 18/10/2009
Português
Relevância na Pesquisa
958.64484%
While in the early 90s High Energy Physics (HEP) lead the computing industry
by establishing the HTTP protocol and the first web-servers, the long
time-scale for planning and building modern HEP experiments has resulted in a
generally slow adoption of emerging computing technologies which rapidly become
commonplace in business and other scientific fields. I will overview some of
the fundamental computing problems in HEP computing and then present the
current state and future potential of employing new computing technologies in
addressing these problems.; Comment: To be published in the proceedings of DPF-2009, Detroit, MI, July
2009, eConf C090726
Link permanente para citações:
High-energy physics and cosmological perturbations: observing new physics at large scales
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 10/12/2013
Português
Relevância na Pesquisa
962.1753%
#High Energy Physics - Theory#Astrophysics - Cosmology and Nongalactic Astrophysics#General Relativity and Quantum Cosmology
Correlators of primordial perturbations could provide us with the signatures
of physics at earlier times/higher momentum scales than inflation. The
key-mechanisms are the interference and cumulation in time related to the
interplay of negative- and positive-frequency components of fields and energy
density generated by the high-momentum scale physics. Here, we discuss which
signatures are universal for such scenarios, and which ones instead would
distinguish the specific cases (for example modified initial states for
inflationary perturbations or modified dispersion relations). We also discuss
the scale dependence of the correlators in presence of these signatures,
especially for some scenarios, and how this could be interesting for
observations.; Comment: 7 pages. Prepared for the proceedings of the European Physical
Society Conference on High Energy Physics EPS-HEP2013, 18-24 July 2013,
Stockholm, Sweden
Link permanente para citações:
FPGA based High Speed Data Acquisition System for High Energy Physics Application
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 30/03/2015
Português
Relevância na Pesquisa
960.69945%
#Physics - Instrumentation and Detectors#Computer Science - Hardware Architecture#High Energy Physics - Experiment
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.
Link permanente para citações:
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
Português
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.
Link permanente para citações:
Development of CMOS pixel sensors for tracking and vertexing in high energy physics experiments
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 10/02/2014
Português
Relevância na Pesquisa
958.82586%
CMOS pixel sensors (CPS) represent a novel technological approach to building
charged particle detectors. CMOS processes allow to integrate a sensing volume
and readout electronics in a single silicon die allowing to build sensors with
a small pixel pitch ($\sim 20 \mu m$) and low material budget ($\sim 0.2-0.3\%
X_0$) per layer. These characteristics make CPS an attractive option for
vertexing and tracking systems of high energy physics experiments. Moreover,
thanks to the mass production industrial CMOS processes used for the
manufacturing of CPS the fabrication construction cost can be significantly
reduced in comparison to more standard semiconductor technologies. However, the
attainable performance level of the CPS in terms of radiation hardness and
readout speed is mostly determined by the fabrication parameters of the CMOS
processes available on the market rather than by the CPS intrinsic potential.
The permanent evolution of commercial CMOS processes towards smaller feature
sizes and high resistivity epitaxial layers leads to the better radiation
hardness and allows the implementation of accelerated readout circuits. The
TowerJazz $0.18 \mu m$ CMOS process being one of the most relevant examples
recently became of interest for several future detector projects. The most
imminent of these project is an upgrade of the Inner Tracking System (ITS) of
the ALICE detector at LHC. It will be followed by the Micro-Vertex Detector
(MVD) of the CBM experiment at FAIR. Other experiments like ILD consider CPS as
one of the viable options for flavour tagging and tracking sub-systems.
Link permanente para citações:
Integrated Circuit Design in US High-Energy Physics
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.
Link permanente para citações:
How good are your fits? Unbinned multivariate goodness-of-fit tests in high energy physics
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
961.4255%
#High Energy Physics - Experiment#Nuclear Experiment#Physics - Data Analysis, Statistics and Probability
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
Link permanente para citações:
Advanced Analysis Methods in High Energy Physics
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
Link permanente para citações:
Signatures of very high energy physics in the squeezed limit of the bispectrum (violation of Maldacena's condition)
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
962.1753%
#Astrophysics - Cosmology and Nongalactic Astrophysics#General Relativity and Quantum Cosmology#High Energy Physics - Theory
We investigate the signatures in the squeezed limit of the primordial scalar
bispectrum due to modifications of the standard theory at high energy. In
particular, we consider the cases of modified dispersion relations and/or
modified initial quantum state (both in the Boundary Effective Field Theory and
in the New Physics Hyper-Surface formulations). Using the in-in formalism we
study in details the squeezed limit of the contributions to the bispectrum from
all possible cubic couplings in the effective theory of single-field inflation.
We find general features such as enhancements and/or non-local shape of the
non-Gaussianities, which are relevant, for example, for measurements of the
halo bias and which distinguish these scenarios from the standard one (with
Bunch-Davies vacuum as initial state and standard kinetic terms). We find that
the signatures change according to the magnitude of the scale of new physics,
and therefore several pieces of information regarding high energy physics could
be obtained in case of detection of these signals, especially bounds on the
scales of new physics.; Comment: 37 pages plus bibliography, version matching the one accepted for
publication by JCAP. Increased pedagogical comments, improved presentation
and text...
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
Português
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
Link permanente para citações:
Evolutionary Computation in High Energy Physics
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)
Link permanente para citações:
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
Português
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
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
Link permanente para citações:
Automated Reconstruction of Particle Cascades in High Energy Physics Experiments
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
959.3948%
We present a procedure for reconstructing particle cascades from event data
measured in a high energy physics experiment. For evaluating the hypothesis of
a specific physics process causing the observed data, all possible
reconstruction versions of the scattering process are constructed from the
final state objects. We describe the procedure as well as examples of physics
processes of different complexity studied at hadron-hadron colliders. We
estimate the performance by 20 microseconds per reconstructed decay vertex, and
0.6 kByte per reconstructed particle in the decay trees.; Comment: 8 pages, 2 figures. Submitted to Computational Science & Discovery
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
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
Link permanente para citações: