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Title: Improved isolation of the p-p underlying event based on minimum-bias trigger-associated hadron correlations, Proceedings of the XLIII International Symposium on Multiparticle Dynamics
Creator: Trainor, Thomas, Prindle, Duncan J.
Date: 2013-09-15, 2013-09-15
Publisher: IIT Press
Description: Some aspects of hadron production in p-p collisions remain unresolved, including the low-hadron-momentum structure of high-parton-energy...
Show moreSome aspects of hadron production in p-p collisions remain unresolved, including the low-hadron-momentum structure of high-parton-energy dijets, separation of triggered dijets from the underlying event (UE), the systematics of multiple parton interactions and possible systematic underestimation of dijet contributions to high-energy nuclear collisions. In this study we apply a minimum-bias trigger-associated (TA) correlation analysis to p-p collisions. We extract a hard component from TA correlations that can be compared with measured jet fragment systematics derived from e+-e− collisions. The kinematic limits on jet fragment production may be determined. The same method may be extended to A-A collisions where the role of minimum-bias jets in spectra and correlations is strongly contested.
Sponsorship: IIT College of Science, High Energy Physics Division of Argonne National Laboratory
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Title: UNDERSTANDING UNCERTAINTIES IN RESOLVED PHOTON STRUCTURE
Creator: Zhan, Hengrui
Date: 2017, 2017-07
Description: The construction of a photon collider has been urged, in order to study the properties of the Higgs boson and electroweak symmetry breaking....
Show moreThe construction of a photon collider has been urged, in order to study the properties of the Higgs boson and electroweak symmetry breaking. It would also provide unique possibilities for measurement of fusion to probe the hadronic structure of the photon. One scheme of design for the photon collider is a linear collider. A study shows that resolved photons contribute about 15% of the cross section to Higgs production with a mass of 120 GeV, but estimates of the resolved photon structure have so far varied greatly. Therefore, resolved photon structure is important to measure. This thesis focuses on the determination of the uncertainties of the cross section of bb production for better understanding of resolved photon structure. The principles of a photon collider are reviewed. In this thesis, the simulation tools for the simulation of the cross section of ! bb collision are developed. After that, the method for determination of the uncertainties of cross section is described. A new set of PDFs to explore these uncertainties is produced. The result of the simulation of the cross section and the calculation for the uncertainties of the cross section is presented and discussed in detailed.
M.S. in Physics, July 2017
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Title: HERAFitter - an open source QCD fit framework, Proceedings of the XLIII International Symposium on Multiparticle Dynamics
Creator: Starovitov, Pavel
Date: 2013-09-15, 2013-09-15
Publisher: IIT Press
Description: The patron distribution functions (PDFs) describe the parton content of the proton. They cannot be calculated from the first principle and are...
Show moreThe patron distribution functions (PDFs) describe the parton content of the proton. They cannot be calculated from the first principle and are to be determined empirically by fitting experimental observables to quantum chromodynamics (QCD) predictions. The HERAFitter project aims to provide a framework for QCD analyses of proton structure at leading order (LO), next-to-leading order (NLO) and next-to-next-to-leading (NNLO) orders in perturbative QCD. The framework includes various modules and interfaces enabling a large number of theoretical and methodological options. It also allows to study the impact of the new experimental data on the PDFs from ep, pp and pp̅ scattering processes. The fast development of the project involves active communication with theorists and experimentalist as well as a close collaboration with the main PDF fitting groups. Full information about the project, downloads and documentation can be found in http://herafitter.org.
Sponsorship: IIT College of Science, High Energy Physics Division of Argonne National Laboratory
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Title: Collective dynamics of the p-Pb collisions at the LHC, Proceedings of the XLIII International Symposium on Multiparticle Dynamics
Creator: Broniowski, Wojciech, Bożek, Piotr
Date: 2013-09-15, 2013-09-15
Publisher: IIT Press
Description: We review the signatures for the soft collective dynamics in highest-multiplicity ultrarelativistic p-Pb collisions and show that the effects...
Show moreWe review the signatures for the soft collective dynamics in highest-multiplicity ultrarelativistic p-Pb collisions and show that the effects are well described in a three-stage model, consisting of the event-by-event Glauber initial conditions, viscous 3+1D hydrodynamics, and statistical hadronization. In particular, we discuss the ridges in two-particle correla- tions in the relative azimuth and pseudorapidity, the elliptic and triangular flow coefficients, and the mass hierarchy of observables sensitive to flow.
Sponsorship: IIT College of Science, High Energy Physics Division of Argonne National Laboratory
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Title: Recent Results from RHIC, Proceedings of the XLIII International Symposium on Multiparticle Dynamics
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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Title: BSM searches in multi-objects final states in ATLAS, Proceedings of the XLIII International Symposium on Multiparticle Dynamics
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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Title: Recent developments in Monte Carlo simulations, Proceedings of the XLIII International Symposium on Multiparticle Dynamics
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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$Diffraction at the LHC$

Title: Diffraction at the LHC, Proceedings of the XLIII International Symposium on Multiparticle Dynamics
Creator: Csanád, M.
Date: 2013-09-15, 2013-09-15
Publisher: IIT Press
Description: Proton-proton collisions at the LHC can be classified as elastic, non-diffractive, and diffractive. In this paper we discuss various...
Show moreProton-proton collisions at the LHC can be classified as elastic, non-diffractive, and diffractive. In this paper we discuss various measurements of these above processes at various LHC experiments. We report about the total proton-proton cross-section measurements, about the analysis of diffractive events and also about the pseudorapidity distribution in inelastic events.
Sponsorship: IIT College of Science, High Energy Physics Division of Argonne National Laboratory
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Title: Low-energy exclusive cross sections and inclusive production of identified charged hadrons with Babar, Proceedings of the XLIII International Symposium on Multiparticle Dynamics
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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Title: INVESTIGATION OF NIOBIUM SURFACE STRUCTURE AND COMPOSITION FOR IMPROVEMENT OF SUPERCONDUCTING RADIO-FREQUENCY CAVITIES
Creator: Trenikhina, Yulia
Date: 2014, 2014-12
Description: Nano-scale investigation of intrinsic properties of niobium near-surface is a key to control performance of niobium superconducting radio...
Show moreNano-scale investigation of intrinsic properties of niobium near-surface is a key to control performance of niobium superconducting radio-frequency cavities. Mechanisms responsible for the performance limitations and their empirical remedies needs to be justified in order to reproducibly control fabrication of SRF cavities with desired characteristics. The high field Q-slope and mechanism behind its cure (120◦C mild vacuum bake) were investigated by comparison of the samples cut out of the cavities with high and low dissipation regions. Material evolution during mild field Q-slope nitrogen treatment was characterized using the coupon samples as well as samples cut out of nitrogen treated cavity. Evaluation of niobium near-surface state after some typical and novel cavity treatments was accomplished. Various TEM techniques, SEM, XPS, AES, XRD were used for the structural and chemical characterization of niobium near-surface. Combination of thermometry and structural temperature-dependent comparison of the cavity cutouts with different dissipation characteristics revealed precipitation of niobium hydrides to be the reason for medium and high field Q-slopes. Step-by-step effect of the nitrogen treatment processing on niobium surface was studied by analytical and structural characterization of the cavity cutout and niobium samples, which were subject to the treatment. Low concentration nitrogen doping is proposed to explain the benefit of nitrogen treatment. Chemical characterization of niobium samples before and after various surface processing (Electropolishing (EP), 800◦C bake, hydrofluoric acid (HF) rinsing) showed the differences that can help to reveal the microscopic effects behind these treatments as well as possible sources of surface contamination.
Ph.D. in Physics, December 2014
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Title: Particle production at large momentum transfer, Proceedings of the XLIII International Symposium on Multiparticle Dynamics
Creator: Gonçalves, V.p., Sauter, Werner K.
Date: 2013-09-15, 2013-09-15
Publisher: IIT Press
Description: Diffractive particle production in ep collisions and coherent pp interactions is studied assuming that the color singlet t channel exchange...
Show moreDiffractive particle production in ep collisions and coherent pp interactions is studied assuming that the color singlet t channel exchange carries large momentum transfer. The differential and total cross sections for vector meson and photon production are calculated using the non-forward solution of the LO and NLO BFKL equation at high energy and large momentum transfer and the predictions are compared with the DESY HERA data. Moreover, we estimate the rapidity distributions and total cross section for the J/Ψ and ρ production in coherent pp interactions at LHC energies. We predict large rates, which implies that the experimental identification can be feasible at the LHC.
Sponsorship: IIT College of Science, High Energy Physics Division of Argonne National Laboratory
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Title: Large x physics: recent results and future plans, Proceedings of the XLIII International Symposium on Multiparticle Dynamics
Creator: Holt, Roy J.
Date: 2013-09-15, 2013-09-15
Publisher: IIT Press
Description: The valence region is exceedingly important in hadron physics since this region not only defines a hadron but also is an excellent...
Show moreThe valence region is exceedingly important in hadron physics since this region not only defines a hadron but also is an excellent discriminator of nucleon structure models. Present uncertainties in light quark distribution functions at high x could also impact high energy physics. Here we will describe a new generation of experiments at Jefferson Lab that is aimed at the high x region of the nucleon. It is noted that the proposed Electron Ion Collider could explore the high x regime.
Sponsorship: IIT College of Science, High Energy Physics Division of Argonne National Laboratory
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Title: Study of the helix model, Proceedings of the XLIII International Symposium on Multiparticle Dynamics
Creator: Todorova-nová, Ŝárka
Date: 2013-09-15, 2013-09-15
Publisher: IIT Press
Description: The quantum properties of a helix-like shaped QCD string are studied in the context of the semi-classical Lund fragmentation model. It is...
Show moreThe quantum properties of a helix-like shaped QCD string are studied in the context of the semi-classical Lund fragmentation model. It is shown how simple quantization rules combined with the causality considerations in the string fragmentation process describe the mass hierarchy of light pseudoscalar mesons. The quantized helix string model predicts observable quantum effects related to the threshold behaviour of the intrinsic transverse momentum of hadrons, and of the minimal transverse momentum difference between adjacent hadrons.
Sponsorship: IIT College of Science, High Energy Physics Division of Argonne National Laboratory
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Title: IRON INCORPORATION INTO FERROELECTRIC LEAD TITANATE
Creator: Ganegoda, Hasitha
Date: 2012-11-27, 2012-12
Description: Incorporation of iron into ferroelectric lead titanate with ABO3 perovskite structure is widely utilized to fabricate materials with...
Show moreIncorporation of iron into ferroelectric lead titanate with ABO3 perovskite structure is widely utilized to fabricate materials with ferroelectric and ferromagnetic order. These solid solutions exhibit room temperature ferromagnetic properties at iron concentration as low as 1 mole%. Iron (Fe3+) is highly compatible with titanium (Ti4+) in ionic radii and obviously incompatible in the valence state. Magnetoelectric coupling has been observed in 50 mole% Fe substituted lead titanate. The molecular mixing of precursor materials in wet chemical synthesis such as sol-gel has advantage over conventional solid state sintering in achieving higher solubility of the substituent. A series of Pb(FexTi1−x)O3− solid solution in the composition range x = 0 to 1 has been synthesized using sol-get route, followed by a moderate temperature (700 C) calcination. The structure and properties of samples were characterized using x-ray diffraction (XRD), x-ray absorption spectroscopy (XAS), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDX), dielectric spectroscopy, Raman spectroscopy, and magnetic measurements. SEM results indicated a gradual change in sample morphology, changing from individual particles to nano-aggregates with Fe concentration. EDX confirmed uniform distribution of dopants when Fe concentration x 0.3 and Fe concentration close to nominal composition with possibility of lead loss. XRD results indicated a rapid reduction of tetragonal distortion upon Fe substitution, Fe solubility limit of 10 mole%, and PbFe12O19 impurity phase formation at compositions x 0.4. XAS clearly indicated that Ti prefers a 6 coordinated distorted oxygen octahedra and Fe is surrounded by 5 oxygens situated at a similar distance. Other measurements suggested that ferroelectric and ferromagnetic ordering may arise in Ti-rich and Fe-rich phases, respectively. None of the samples below x = 0.2 was found to be ferromagnetic at room temperature.
PH.D in Physics, December 2012
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Title: Measurement of the charged kaon correlations at small relative momentum in the SELEX experiment, Proceedings of the XLIII International Symposium on Multiparticle Dynamics
Creator: Nigmatkulov, Grigory
Date: 2013-09-15, 2013-09-15
Publisher: IIT Press
Description: We report the first measurement of charged kaon Bose–Einstein correlations produced by 600 GeV/c Σ−, π− and 540 GeV/c p beams in the SELEX...
Show moreWe report the first measurement of charged kaon Bose–Einstein correlations produced by 600 GeV/c Σ−, π− and 540 GeV/c p beams in the SELEX experiment. The SELEX (E781) experiment at Fermilab is a fixed target three–stage magnetic spectrometer designed for study hadroproduction at high acceptance for forward interactions (xF ≥ 0.1). One–dimensional charged kaon correlation functions were obtained for all three beams and three pair transverse momentum ranges. The femtoscopic parameters for the radii and correlation strength of the kaon source were extracted. The fit results show the decrease of the emission source radii with the increase of the pair transverse momentum.
Sponsorship: IIT College of Science, High Energy Physics Division of Argonne National Laboratory
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Title: Future physics: A personal view, Proceedings of the XLIII International Symposium on Multiparticle Dynamics
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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Title: Kaon Freeze-out Dynamics in √sNN=200 GeV Au+Au Collisions at RHIC, Proceedings of the XLIII International Symposium on Multiparticle Dynamics
Creator: Šumbera, Michal
Date: 2013-09-15, 2013-09-15
Publisher: IIT Press
Description: Measurements of three-dimensional correlation functions of like-sign low transverse momentum kaon pairs from Au+Au collisions at top RHIC...
Show moreMeasurements of three-dimensional correlation functions of like-sign low transverse momentum kaon pairs from Au+Au collisions at top RHIC energy √sNN =200 GeV are presented. The extracted kaon source function is narrower than the pion one and does not have the long tail along the pair transverse momentum direction. This indicates a much smaller role of long-lived resonance decays and/or of the emission duration on kaon emission. Three-dimensional Gaussian shape of the kaon source function can be adequately reproduced by Therminator simulations with resonance contributions taken into account. Comparison to pion data at the same energy reveals that the kaon Gaussian radii in the outward and sideward directions scale with the transverse mass mT. In the longitudinal direction, unlike at lower SPS energies, the Gaussian radii do not seem to follow the exact mT scaling between kaons and pions.
Sponsorship: IIT College of Science, High Energy Physics Division of Argonne National Laboratory
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Title: Measurement of the strong coupling αS from the 3-jet rate in e⁺ e⁻ annihilation using JADE data, Proceedings of the XLIII International Symposium on Multiparticle Dynamics
Creator: Kluth, S.
Date: 2013-09-15, 2013-09-15
Publisher: IIT Press
Description: We describe a measurement of the strong coupling αS(MZ₀ ) from the 3-jet rate in hadronic final states of e⁺ e⁻ annihilation recorded with the...
Show moreWe describe a measurement of the strong coupling αS(MZ₀ ) from the 3-jet rate in hadronic final states of e⁺ e⁻ annihilation recorded with the JADE detector at centre-of-mass energies of 14 to 44 GeV. The jets are reconstructed with the Durham jet clustering algorithm. The JADE 3-jet rate data are compared with QCD predictions in NNLO combined with resummed calculations. We find good agreement between the data and the prediction and extract αS(MZ₀ ) = 0.1199±0.0010(stat.)±0.0021(exp.)±0.0054(had.)±0.0007(theo.) .
Sponsorship: IIT College of Science, High Energy Physics Division of Argonne National Laboratory
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Title: Parton distributions and event generators, Proceedings of the XLIII International Symposium on Multiparticle Dynamics
Creator: Carrazza, Stefano, Forte, Stefano, Rojo, Juan
Date: 2013-09-15, 2013-09-15
Publisher: IIT Press
Description: We present the implementation within the Pythia8 event generator of a set of parton distributions based on NNPDF methodology. We construct a...
Show moreWe present the implementation within the Pythia8 event generator of a set of parton distributions based on NNPDF methodology. We construct a set of leading-order parton distributions with QED corrections, NNPDF2.3QED LO set, based on the same data as the previous NNPDF2.3 NLO and NNLO PDF sets. We compare this PDF set to its higher-order counterparts, we discuss its implementation as an internal set in Pythia8, and we use it to study some of the phenomenological implications of photon-initiated contributions for dilepton production at hadron colliders.
Sponsorship: IIT College of Science, High Energy Physics Division of Argonne National Laboratory
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Title: Overview of Higgs results from CMS, Proceedings of the XLIII International Symposium on Multiparticle Dynamics
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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