Hadron Production by [math Display

Hadron Production by [math Display PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 969

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Measurements of multihadron production in ee− annihilation at center-of-mass energies between 2.6 and 7.8 GeV are presented. Aside from the narrow resonances [psi](3095) and [psi](3684), the total hadronic cross section is found to be approximately 2.7 times the cross section for the production of muon pairs at c.m. energies below 3.7 GeV and 4.3 times the muon-pair cross section at c.m. energies above 5.5 GeV. Complicated structure is found at intermediate energies. Charged-particle multiplicities and inclusive momentum distributions are presented.

Hadron Production by [math Display

Hadron Production by [math Display PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 969

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Book Description
Measurements of multihadron production in ee− annihilation at center-of-mass energies between 2.6 and 7.8 GeV are presented. Aside from the narrow resonances [psi](3095) and [psi](3684), the total hadronic cross section is found to be approximately 2.7 times the cross section for the production of muon pairs at c.m. energies below 3.7 GeV and 4.3 times the muon-pair cross section at c.m. energies above 5.5 GeV. Complicated structure is found at intermediate energies. Charged-particle multiplicities and inclusive momentum distributions are presented.

Measurement of the [math Display

Measurement of the [math Display PDF Author:
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ISBN:
Category :
Languages : en
Pages :

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The ZZ production cross section in proton-proton collisions at 13 TeV center-of-mass energy is measured using 3.2 fb-1 of data recorded with the ATLAS detector at the Large Hadron Collider. The considered Z boson candidates decay to an electron or muon pair of mass 66-116 GeV. The cross section is measured in a fiducial phase space reflecting the detector acceptance. It is also extrapolated to a total phase space for Z bosons in the same mass range and of all decay modes, giving 16.7+2.2-2.0(stat)+0.9-0.7(syst)+1.0-0.7(lumi) pb. Lastly, the results agree with standard model predictions.

Measurement of Electrons from Semileptonic Heavy-flavor Hadron Decays in [math Display

Measurement of Electrons from Semileptonic Heavy-flavor Hadron Decays in [math Display PDF Author:
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ISBN:
Category :
Languages : en
Pages :

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We measured the pT-differential production cross section of electrons from semileptonic decays of heavy-flavor hadrons at midrapidity in proton-proton collisions and at √s=2.76 TeV in the transverse momentum range 0.5

Nuclear Science Abstracts

Nuclear Science Abstracts PDF Author:
Publisher:
ISBN:
Category : Nuclear energy
Languages : en
Pages : 538

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Mathematics and Computation

Mathematics and Computation PDF Author: Avi Wigderson
Publisher: Princeton University Press
ISBN: 0691189137
Category : Computers
Languages : en
Pages : 434

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Book Description
An introduction to computational complexity theory, its connections and interactions with mathematics, and its central role in the natural and social sciences, technology, and philosophy Mathematics and Computation provides a broad, conceptual overview of computational complexity theory—the mathematical study of efficient computation. With important practical applications to computer science and industry, computational complexity theory has evolved into a highly interdisciplinary field, with strong links to most mathematical areas and to a growing number of scientific endeavors. Avi Wigderson takes a sweeping survey of complexity theory, emphasizing the field’s insights and challenges. He explains the ideas and motivations leading to key models, notions, and results. In particular, he looks at algorithms and complexity, computations and proofs, randomness and interaction, quantum and arithmetic computation, and cryptography and learning, all as parts of a cohesive whole with numerous cross-influences. Wigderson illustrates the immense breadth of the field, its beauty and richness, and its diverse and growing interactions with other areas of mathematics. He ends with a comprehensive look at the theory of computation, its methodology and aspirations, and the unique and fundamental ways in which it has shaped and will further shape science, technology, and society. For further reading, an extensive bibliography is provided for all topics covered. Mathematics and Computation is useful for undergraduate and graduate students in mathematics, computer science, and related fields, as well as researchers and teachers in these fields. Many parts require little background, and serve as an invitation to newcomers seeking an introduction to the theory of computation. Comprehensive coverage of computational complexity theory, and beyond High-level, intuitive exposition, which brings conceptual clarity to this central and dynamic scientific discipline Historical accounts of the evolution and motivations of central concepts and models A broad view of the theory of computation's influence on science, technology, and society Extensive bibliography

Probing Triple-Higgs Productions Via [math Display

Probing Triple-Higgs Productions Via [math Display PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Book Description
We report that the quartic self-coupling of the Standard Model Higgs boson can only be measured by observing the triple-Higgs production process, but it is challenging for the LHC Run 2 or International Linear Collider (ILC) at a few TeV because of its extremely small production rate. In this paper, we present a detailed Monte Carlo simulation study of the triple-Higgs production through gluon fusion at a 100 TeV hadron collider and explore the feasibility of observing this production mode. We focus on the decay channel HHH 2!b\bar{b}$$b\bar{b}$[gamma][gamma], investigating detector effects and optimizing the kinematic cuts to discriminate the signal from the backgrounds. Our study shows that, in order to observe the Standard Model triple-Higgs signal, the integrated luminosity of a 100 TeV hadron collider should be greater than 1.8×104 ab1. We also explore the dependence of the cross section upon the trilinear ([lambda]3) and quartic ([lambda]4) self-couplings of the Higgs. Ultimately, we find that, through a search in the triple-Higgs production, the parameters [lambda]3 and [lambda]4 can be restricted to the ranges [−1,5] and [−20,30], respectively. We also examine how new physics can change the production rate of triple-Higgs events. For example, in the singlet extension of the Standard Model, we find that the triple-Higgs production rate can be increased by a factor of O(10).

Measurements of [math Display

Measurements of [math Display PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :

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This study presents measurements of W±Z production in pp collisions at a center-of-mass energy of 8 TeV. The gauge bosons are reconstructed using their leptonic decay modes into electrons and muons. The data were collected in 2012 by the ATLAS experiment at the Large Hadron Collider and correspond to an integrated luminosity of 20.3 fb-1. The measured inclusive cross section in the detector fiducial region is [sigma]W±Z→l'[nu]ll = 35.1 ± 0.9(stat) ± 0.8(sys) ± 0.8(lumi) fb, for one leptonic decay channel. In comparison, the next-to-leading-order Standard Model expectation is 30.0 ± 2.1 fb. Cross sections for W+Z and W-Z production and their ratio are presented as well as differential cross sections for several kinematic observables. Limits on anomalous triple gauge boson couplings are derived from the transverse mass spectrum of the W±Z system. From the analysis of events with a W and a Z boson associated with two or more forward jets an upper limit at 95% confidence level on the W±Z scattering cross section of 0.63 fb, for each leptonic decay channel, is established, while the Standard Model prediction at next-to-leading order is 0.13 ± 0.01 fb. Limits on anomalous quartic gauge boson couplings are also extracted.

Evidence for Electroweak Production of [math Display

Evidence for Electroweak Production of [math Display PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :

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This paper presents the first study of W± W± jj, same-electric-charge diboson production in association with two jets, using 20.3 fb−1 of proton-proton collision data at √s= 8 TeV recorded by the ATLAS detector at the Large Hadron Collider. Events with two reconstructed same-charge leptons (e± e± , e± [mu]± , and [mu]± [mu]± ) and two or more jets are analyzed. Production cross sections are measured in two fiducial regions, with different sensitivities to the electroweak and strong production mechanisms. First evidence for W± W± jj production and electroweak-only W± W± jj production is observed with a significance of 4.5 and 3.6 standard deviations, respectively. The measured production cross sections are in agreement with standard model predictions. Limits at 95% confidence level are set on anomalous quartic gauge couplings.

Searches for Higgs Boson Pair Production in the [math Display

Searches for Higgs Boson Pair Production in the [math Display PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Book Description
Searches for both resonant and nonresonant Higgs boson pair production are performed in the hh → bb[tau][tau], [gamma][gamma]WW* final states using 20.3 fb-1 of pp collision data at a center-of-mass energy of 8 TeV recorded with the ATLAS detector at the Large Hadron Collider. No evidence of their production is observed and 95% confidence-level upper limits on the production cross sections are set. These results are then combined with the published results of the hh → [gamma][gamma]bb, bbbb analyses. An upper limit of 0.69 (0.47) pb on the nonresonant hh production is observed (expected), corresponding to 70 (48) times the SM gg → hh cross section. For production via narrow resonances, cross-section limits of hh production from a heavy Higgs boson decay are set as a function of the heavy Higgs boson mass. The observed (expected) limits range from 2.1 (1.1) pb at 260 GeV to 0.011 (0.018) pb at 1000 GeV. In addition, these results are interpreted in the context of two simplified scenarios of the Minimal Supersymmetric Standard Model.

Physics Briefs

Physics Briefs PDF Author:
Publisher:
ISBN:
Category : Physics
Languages : en
Pages : 1118

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Book Description