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Magnetic Impulse Record Member, Magnetic Material and Method of Making Magnetic Material
Sponsorship: Armour Research Foundation of Illinois Institute of Technology, United States Patent
Vibrationless Pneumatic Impact Tool
Sponsorship: Armour Research Foundation of Illinois Institute of Technology, United States Patent
Magnetic Recorder Head
Sponsorship: Armour Research Foundation, United States Patent
Nontwisting Paramagnetic Record Wire
Sponsorship: Armour Research Foundation of Illinois Institute of Technology, United States Patent
Hadronic final states in high-pT QCD at CDF
The heavy quark content associated with gauge boson production is of great interest to studies of QCD. These events probe the gluon and heavy-quark parton distribution functions of the proton, and also provide a measurement of the rate of final state gluon splitting to heavy favor. In addition, gauge boson plus heavy quark events are representative of backgrounds to Higgs, single top, and supersymmetric particle searches. Recent work with the CDF II detector at the Fermilab Tevatron has measured the cross-section of several gauge boson plus heavy flavor production processes, including the first Tevatron observation of specific charm process p͞p → W + c. Results are found to be in agreement with NLO predictions that include an enhanced rate of g → c͞c =b͞b splitting. Lastly, a new analysis promises to probe a lower pT (c) region than has yet been explored, by fully reconstructing D* → D^0 (Kπ)π decays in the full CDF dataset (9:7 fb^1)., Sponsorship: IIT College of Science, High Energy Physics Division of Argonne National Laboratory
Overview of Higgs results from CMS
Sponsorship: 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.
Boosted heavy particles and jet substructure with the CMS detector
In 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
Minimum-bias angular and trigger-associated correlations from 200 GeV p-p collisions: jets, flows, centrality, and the underlying event
The 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
BSM searches in multi-objects final states in ATLAS
Recent 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
Physics implications of correlation data from the RHIC and LHC heavy-ion programs
Two-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
Influence of the target on multiparticle production in the forward domain in p+Pb collisions at 158 GeV
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. 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
Measurement of anisotropic radial flow rapidity
Using 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
The potential importance of low luminosity and high energy at the LHC
Low 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
Low-energy exclusive cross sections and inclusive production of identified charged hadrons with Babar
Recent 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
Recent results on vector boson production in association with jets with the CMS detector
The 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
Recent developments in Monte Carlo simulations
This 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
Recent results from the search for the critical point of strongly interacting matter at the CERN SPS
Recent 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
The phase diagram of QCD from lattice simulations
Numerical 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
Particle production sources in heavy ion collisions at RHIC and LHC
A 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
STAR Results from the RHIC Beam Energy Scan
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 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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