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Title: Overview of Higgs results from CMS
Creator: Merkel, Petra
Date: 2013-09-15, 2013-09-15
Publisher: IIT Press
Description: Sponsorship: IIT College of Science, High Energy Physics Division of Argonne National Laboratory
In this article we present an overview of...
Show moreSponsorship: IIT College of Science, High Energy Physics Division of Argonne National Laboratory
In this article we present an overview of Higgs boson results from the CMS Collaboration as presented at the ISMD13 conference.
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Collection: Proceedings of the XLIII International Symposium on Multiparticle Dynamics

Title: Boosted heavy particles and jet substructure with the CMS detector
Creator: Marchesini, Ivan
Date: 2013-09-15, 2013-09-15
Publisher: IIT Press
Description: In the last years, the understanding of jets and jet substructure has become increasingly important, in particular in the context of new...
Show moreIn the last years, the understanding of jets and jet substructure has become increasingly important, in particular in the context of new physics searches. Many new physics models involve highly boosted hadronically-decaying particles, which result in jet-like objects with large masses and an intrinsic substructure. Discrimination of these heavy jets from ordinary quark and gluon jets is possible through a plethora of new techniques. The understanding of jets can be exploited also for the identification of pileup jets and for the discrimination between quark jets and gluon jets. A sampling of these techniques is discussed together with their validation on collider data recorded in proton-proton collisions at √s = 8TeV with the CMS detector in the year 2012. The commissioning in the boosted regime of algorithms used to identify jets originating from bottom quarks is also discussed. Many studies have highlighted the potential of using jet substructure techniques to improve the sensitivity in physics searches. An overview of recent CMS results employing these techniques is presented.
Sponsorship: IIT College of Science, High Energy Physics Division of Argonne National Laboratory
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Collection: Proceedings of the XLIII International Symposium on Multiparticle Dynamics

Title: Minimum-bias angular and trigger-associated correlations from 200 GeV p-p collisions: jets, flows, centrality, and the underlying event
Creator: Prindle, D.
Date: 2013-09-15, 2013-09-15
Publisher: IIT Press
Description: The mechanisms leading to the hadronic final state of high-energy proton-proton collisions remain an unresolved issue at the RHIC and LHC. A...
Show moreThe mechanisms leading to the hadronic final state of high-energy proton-proton collisions remain an unresolved issue at the RHIC and LHC. A substantial contribution to the hadronic final state from minimum-bias (MB) jets is dominated by non-perturbative processes and may provide the common base for any high-energy dijet. Observation of a same-side (on azimuth)“ridge” in LHC p-p collisions suggests to some that hydrodynamic flows may play a role in that small system at higher energies. The issue of p-p centrality vs triggered jets has emerged in the context of gluon trans- verse distributions in the proton inferred from DIS data. Attempts have been made to isolate and study the underlying event (UE) complementary to triggered dijets, and it is suggested that multiple parton interactions may contribute to the UE. Reference [1] considered theoretical and experimental results for UE systematics and p-p centrality in the context of a two-component (soft+hard) model derived from single-particle pt spectrum nch systematics. The study concluded that there may be a substantial contribution to the UE from the triggered dijet and that p-p centrality is not controlled significantly by a jet trigger condition (if p-p centrality is relevant at all). Further study of two-particle correlations in p-p collisions was called for, particularly the nch dependence of MB correlations. We report a comprehensive study of MB (no pt cuts) angular correlations and trigger-associated (TA) yt correlations (transverse rapidity yt = ln[(mt + pt)/mπ]) from 200 GeV p-p collisions. Angular correlations are characterized by 2D model fits that accurately distinguish among proton dissociation structure (soft), jet-related structure (hard) and a nonjet azimuth quadrupole. All angular correlations are simply represented by a (2+1)-component model. The hard and quadrupole component scale simply with the soft-component multiplicity ns, clarifying the role of centrality and the eikonal model in p-p collisions. 2D TA correlations project to a marginal 1D trigger spectrum that can be simply predicted from pt spec- trum nch dependence. 2D TA distributions can then be processed to reveal MB jet fragment (hard component) systematics comparable to measured fragmentation functions. Hard-component azimuth dependence relative to the trigger relates to UE studies. From TA analysis we can establish the kinematic limits of jet fragment production in p-p collisions.
Sponsorship: IIT College of Science, High Energy Physics Division of Argonne National Laboratory
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Collection: Proceedings of the XLIII International Symposium on Multiparticle Dynamics

Title: BSM searches in multi-objects final states in ATLAS
Creator: Cornelissen, Thijs
Date: 2013-09-15, 2013-09-15
Publisher: IIT Press
Description: Recent results on searches for new physics from Run 1 of the Large Hadron Collider are reported. The ATLAS experiment has already collected...
Show moreRecent results on searches for new physics from Run 1 of the Large Hadron Collider are reported. The ATLAS experiment has already collected more than 20 fb−1 of integrated luminosity, allowing for a large number of new phenomena searches in many different final states. No deviations from the Standard Model expectations are found, and corresponding constraints on physics beyond the Standard Model are obtained.
Sponsorship: IIT College of Science, High Energy Physics Division of Argonne National Laboratory
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Collection: Proceedings of the XLIII International Symposium on Multiparticle Dynamics

Title: Physics implications of correlation data from the RHIC and LHC heavy-ion programs
Creator: Ray, R. L.
Date: 2013-09-15, 2013-09-15
Publisher: IIT Press
Description: Two-dimensional angular correlation data from the STAR experiment at RHIC and from the LHC experiments provide critical information about...
Show moreTwo-dimensional angular correlation data from the STAR experiment at RHIC and from the LHC experiments provide critical information about dynamical processes in relativistic heavy-ion collisions. The principal correlation structures of interest are a broad jet-related peak at small relative azimuth (φ) extending to large relative pseudorapidity (η), the dijet ridge at large relative azimuth, and an independent double ridge on φ represented by a quadrupole function. The broad peak at small relative azimuth has been attributed, in large part, to initial-state fluctuations and hydrodynamic flow which produce higher-order harmonics on φ. That conjecture is challenged in this paper. It is shown that the net effect of additional higher harmonic model elements is to describe small, non-Gaussian (NG) shapes in the broad jet-related peak. The quadrupole correlation, which is also conventionally attributed to hydrodynamic flow, is considered within the Balitsky - Fadin - Kuraev - Lipatov (BFKL) Pomeron framework. Preliminary results using this model for the quadrupole correlation for particle production from 200 GeV p + p collisions are shown to be consistent with recent data from STAR.
Sponsorship: IIT College of Science, High Energy Physics Division of Argonne National Laboratory
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Collection: Proceedings of the XLIII International Symposium on Multiparticle Dynamics

Title: Influence of the target on multiparticle production in the forward domain in p+Pb collisions at 158 GeV
Creator: Rybczyński, Maciej
Date: 2013-09-15, 2013-09-15
Publisher: IIT Press
Description: In this talk we show the influence of the target on multiparticle production in the forward hemisphere in p+Pb collisions at top SPS energy....
Show moreIn this talk we show the influence of the target on multiparticle production in the forward hemisphere in p+Pb collisions at top SPS energy. The multiplicity distributions appear to be almost target independent in the projectile fragmentation domain and the effect of fluctuations of the number of target participants is not seen in the projectile fragmentation region. We compare the obtained results with those for p+p interactions and predictions of models.
Sponsorship: IIT College of Science, High Energy Physics Division of Argonne National Laboratory
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Collection: Proceedings of the XLIII International Symposium on Multiparticle Dynamics

Title: Measurement of anisotropic radial flow rapidity
Creator: Wu, Yuafang, Li, Lin, Li, Na
Date: 2013-09-15, 2013-09-15
Publisher: IIT Press
Description: Using the sample of Au + Au collisions at 200 GeV generated by the AMPT with string melting model, the anisotropic amplitudes of azimuthal...
Show moreUsing the sample of Au + Au collisions at 200 GeV generated by the AMPT with string melting model, the anisotropic amplitudes of azimuthal distributions of total transverse momentum, mean radial (transverse) momentum, and multiplicity are first presented and compared. It shows that the azimuthal distribution of mean radial momentum well characterizes the radial expansion. So a measurement of the azimuthal distribution of mean transverse (radial) rapidity of final state particles is suggested. We further show that the isotropic part of the suggested distribution is the combination of isotropic radial expansion and thermal motion. The anisotropic amplitude characterizes the anisotropic radial flow, and coincides with the parameter of anisotropic radial flow rapidity extracted from a generalized blast-wave parametrization.
Sponsorship: IIT College of Science, High Energy Physics Division of Argonne National Laboratory
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Collection: Proceedings of the XLIII International Symposium on Multiparticle Dynamics

Title: The potential importance of low luminosity and high energy at the LHC
Creator: White, Alan R.
Date: 2013-09-15, 2013-09-15
Publisher: IIT Press
Description: Low luminosity runs at higher LHC energy could provide definitive evidence for an electroweak scale sextet quark sector of QCD that produces...
Show moreLow luminosity runs at higher LHC energy could provide definitive evidence for an electroweak scale sextet quark sector of QCD that produces electroweak symmetry breaking and dark matter within the bound-state S-Matrix of QUD - a massless, weak coupling, infra-red fixed-point, SU(5) field theory that might underly and unify the full Standard Model.
Sponsorship: IIT College of Science, High Energy Physics Division of Argonne National Laboratory
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Collection: Proceedings of the XLIII International Symposium on Multiparticle Dynamics

Title: Low-energy exclusive cross sections and inclusive production of identified charged hadrons with Babar
Creator: Gary, J. William
Date: 2013-09-15, 2013-09-15
Publisher: IIT Press
Description: Recent measurements of exclusive hadronic cross sections from the Babar Collaboration at SLAC are presented. Specifically, we present results...
Show moreRecent measurements of exclusive hadronic cross sections from the Babar Collaboration at SLAC are presented. Specifically, we present results on the e⁺e⁻ → K⁺K⁻(γ), p̅p, KₛKₗ, KₛKₗπ⁺π⁻ , KₛKₛπ⁺π⁻, and KₛKₛK⁺K⁻ cross sections performed using events with initial-state photon radiation, which allows the cross sections to be measured at low energy and over an extended energy range. In addition, we present results on the inclusive momentum spectra of identified charged pions, kaons, and protons at the fixed center-of-mass energy of 10.54 GeV, allowing new tests of QCD.
Sponsorship: IIT College of Science, High Energy Physics Division of Argonne National Laboratory
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Collection: Proceedings of the XLIII International Symposium on Multiparticle Dynamics

Title: Recent results on vector boson production in association with jets with the CMS detector
Creator: Cornelis, Tom
Date: 2013-09-15, 2013-09-15
Publisher: IIT Press
Description: The production of weak vector bosons in association with jets and their properties are intensively studied using proton-proton collision data...
Show moreThe production of weak vector bosons in association with jets and their properties are intensively studied using proton-proton collision data collected with the CMS detector. In this proceedings, we will show the cross section measurement of the electroweak production of a Z boson in association with 2 jets at √s = 8 TeV, including a new data-driven approach and studies on the hadronic activity in the region between the two tagging jets. The azimuthal correlations and event shapes in Z + jets events at √s= 7 TeV are also presented.
Sponsorship: IIT College of Science, High Energy Physics Division of Argonne National Laboratory
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Collection: Proceedings of the XLIII International Symposium on Multiparticle Dynamics

Title: Recent developments in Monte Carlo simulations
Creator: Thompson, Jennifer M.
Date: 2013-09-15, 2013-09-15
Publisher: IIT Press
Description: This talk outlines the current status of Monte Carlo simulations in particle physics. It demonstrates the implementation of automated NLO...
Show moreThis talk outlines the current status of Monte Carlo simulations in particle physics. It demonstrates the implementation of automated NLO contributions to matrix elements. The matching methods MC@NLO and POWHEG are outlined and results using various NLO tools are presented. The first plots from POWHEG showing the matching of NNLO matrix elements to the parton shower are also presented.
Sponsorship: IIT College of Science, High Energy Physics Division of Argonne National Laboratory
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Collection: Proceedings of the XLIII International Symposium on Multiparticle Dynamics

Title: Recent results from the search for the critical point of strongly interacting matter at the CERN SPS
Creator: Seyboth, Peter
Date: 2013-09-15, 2013-09-15
Publisher: IIT Press
Description: Recent searches at the CERN SPS for evidence of the critical point of strongly interacting matter are discussed. Experimental results on...
Show moreRecent searches at the CERN SPS for evidence of the critical point of strongly interacting matter are discussed. Experimental results on theroretically expected signatures, such as event-to-event fluctuations of the particle multiplicity and the average transverse momentum as well as intermittency in particle production are presented.
Sponsorship: IIT College of Science, High Energy Physics Division of Argonne National Laboratory
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Collection: Proceedings of the XLIII International Symposium on Multiparticle Dynamics

Title: The phase diagram of QCD from lattice simulations
Creator: D'elia, Massimo
Date: 2013-09-15, 2013-09-15
Publisher: IIT Press
Description: Numerical simulations of Quantum Chromodynamics on a space-time lattice represent the best non-perturbative tool to explore the QCD phase...
Show moreNumerical simulations of Quantum Chromodynamics on a space-time lattice represent the best non-perturbative tool to explore the QCD phase diagram and the behavior of strong interactions under extreme conditions. We review the present status of the field and discuss some recent results.
Sponsorship: IIT College of Science, High Energy Physics Division of Argonne National Laboratory
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Collection: Proceedings of the XLIII International Symposium on Multiparticle Dynamics

Title: Particle production sources in heavy ion collisions at RHIC and LHC
Creator: Wolschin, Georg
Date: 2013-09-15, 2013-09-15
Publisher: IIT Press
Description: A nonequilibrium statistical relativistic diffusion model (RDM) with three sources is applied to the analysis of charged-hadron distributions...
Show moreA nonequilibrium statistical relativistic diffusion model (RDM) with three sources is applied to the analysis of charged-hadron distributions in Au–Au collisions at RHIC energies, in Pb–Pb collisions at the current LHC energy of 2.76 TeV, and in p–Pb at 5.02 TeV. The relative sizes of the particle production sources at RHIC and LHC energies are investigated in pseudorapidity space as functions of incident energy. The midrapidity source that arises mostly from gluon-gluon collisions becomes more important than the fragmentation sources as the energy increases from RHIC to LHC.
Sponsorship: IIT College of Science, High Energy Physics Division of Argonne National Laboratory
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Collection: Proceedings of the XLIII International Symposium on Multiparticle Dynamics

Title: STAR Results from the RHIC Beam Energy Scan
Creator: Wang, Hui
Date: 2013-09-15, 2013-09-15
Publisher: IIT Press
Description: The Beam Energy Scan Program is launched by RHIC to study the QCD phase diagram. The goal is to explore the possible QCD phase boundary and...
Show moreThe Beam Energy Scan Program is launched by RHIC to study the QCD phase diagram. The goal is to explore the possible QCD phase boundary and search for possible QCD critical point. In 2010 and 2011, experiments collected data at √sNN=7.7, 11.5, 19.6, 27, 39 and 62.4 GeV, covering a wide range of baryon chemical potential from μB 420 to 70 MeV. In this presentation, we will report some latest results of the Beam Energy Scan Program from the STAR collaboration.
Sponsorship: IIT College of Science, High Energy Physics Division of Argonne National Laboratory
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Collection: Proceedings of the XLIII International Symposium on Multiparticle Dynamics

Title: High-order cumulants from the 3D O(1) and O(4) spin models
Creator: Pan, Xue, Wu, Yuafang, Chen, X. S., Chen, Lizhu
Date: 2013-09-15, 2013-09-15
Publisher: IIT Press
Description: We simulate the 3D O(1) (Ising) and O(4) spin models by the Monte Carlo method. Interesting high-order cumulants from the 3D Ising and O(4)...
Show moreWe simulate the 3D O(1) (Ising) and O(4) spin models by the Monte Carlo method. Interesting high-order cumulants from the 3D Ising and O(4) universality classes are presented and discussed. They all show the non-monotonic or sign change behavior. The critical behavior is instructive to that of the high-order cumulants of the net baryon number in the QCD phase transitions. Maybe it’s difficult to distinguish the universality classes by the high-order cumulants in the heavy ion collisions.
Sponsorship: IIT College of Science, High Energy Physics Division of Argonne National Laboratory
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Collection: Proceedings of the XLIII International Symposium on Multiparticle Dynamics

$Diffractive cross sections implemented in PYTHIA8-MBR VS LHC results$

Title: Diffractive cross sections implemented in PYTHIA8-MBR VS LHC results
Creator: Goulianos, Konstantin
Date: 2013-09-15, 2013-09-15
Publisher: IIT Press
Description: Diffractive cross sections implemented in the pythia8-mbr Monte Carlo simulation are reviewed and compared to results obtained at the Large...
Show moreDiffractive cross sections implemented in the pythia8-mbr Monte Carlo simulation are reviewed and compared to results obtained at the Large Hadron Collider.
Sponsorship: IIT College of Science, High Energy Physics Division of Argonne National Laboratory
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Collection: Proceedings of the XLIII International Symposium on Multiparticle Dynamics

Title: Stochastic mechanism of color confinement
Creator: Kuvshinov, V.
Date: 2013-09-15, 2013-09-15
Publisher: IIT Press
Description: It is shown that in stochastic QCD a vacuum color quark is confined due to the interaction with environment, chaotic dynamics of Yang-Mills...
Show moreIt is shown that in stochastic QCD a vacuum color quark is confined due to the interaction with environment, chaotic dynamics of Yang-Mills-Higgsfields, decoherence of pure color state into mixed white (colorless) state and also squeezed, and entangled states appearance. Critical energy of order-chaos transition is obtained which depends on Higgs boson mass. Stochasticity is the root of color confinement disappearing of color at confinement radius.
Sponsorship: IIT College of Science, High Energy Physics Division of Argonne National Laboratory
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Collection: Proceedings of the XLIII International Symposium on Multiparticle Dynamics

Title: Future physics: A personal view
Creator: Bjorken, James
Date: 2013-09-15, 2013-09-15
Publisher: IIT Press
Description: A personal view of the future of particle physics is presented.
Sponsorship: IIT College of Science, High Energy Physics Division of Argonne...
Show moreA personal view of the future of particle physics is presented.
Sponsorship: IIT College of Science, High Energy Physics Division of Argonne National Laboratory
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Collection: Proceedings of the XLIII International Symposium on Multiparticle Dynamics

Title: Recent Results from RHIC
Creator: Evdokimov, O.
Date: 2013-09-15, 2013-09-15
Publisher: IIT Press
Description: The Relativistic Heavy Ion Collider (RHIC) has opened a new era in experimental nuclear physics. Among the most important discoveries of this...
Show moreThe Relativistic Heavy Ion Collider (RHIC) has opened a new era in experimental nuclear physics. Among the most important discoveries of this new era are the jet quenching phenomenon, the energy loss suffered by a hard scattered parton traversing the medium, and the collective flow, approaching the limit of ideal hydrodynamics. RHIC experiments have introduced a number of novel correlation methods for studies of jets and jet-medium interactions in the high multiplicity environment of ultra-relativistic heavy ion collisions. The di- and multi-hadron correlation techniques have since been quintessential to the understanding of the properties of the created medium in many complementary ways. In this work selected recent results are presented for the RHIC’s top energy collisions at 200 GeV. Di-hadron correlation measurements from Au–Au collisions, illuminating the properties of the hot nuclear medium, are confronted with the recent findings from d–Au data at the same energy. Understanding of initial state properties and collision evolution is tested by unexpected similarities in the di-hadron correlation measurements between the two systems.
Sponsorship: IIT College of Science, High Energy Physics Division of Argonne National Laboratory
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Collection: Proceedings of the XLIII International Symposium on Multiparticle Dynamics

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