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Full-Text Articles in Physics

Manifestation Of The Color Glass Condensate In Particle Production At Rhic, Kirill Tuchin Jan 2005

Manifestation Of The Color Glass Condensate In Particle Production At Rhic, Kirill Tuchin

Kirill Tuchin

We discuss general properties of the Color Glass Condensate. We show that predictions for particle production in p(d)A and AA collisions derived from these properties are in agreement with data collected at RHIC.


Systematic Study Of High-Pt Di-Jet Correlations In Nuclear Collisions With The Phenix Experiment At Rhic , Nathan Conrad Grau Jan 2005

Systematic Study Of High-Pt Di-Jet Correlations In Nuclear Collisions With The Phenix Experiment At Rhic , Nathan Conrad Grau

Retrospective Theses and Dissertations

One major goal of the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory on Long Island, New York, is to create and study the quark-gluon plasma (QGP). This state of matter results from the phase transition of Quantum Chromodynamics (QCD) at extremely high temperature (1012 K) and densities (100 times normal nuclear matter). Au ions are collided in an attempt to increase the temperature necessary to cross the phase boundary. To study the properties of this new matter, high energy jets are used as a probe. Jets are a collimated spray of hadrons resulting from the fragmentation of high-energy ...


Heavy Quark Production By A Quasi-Classical Color Field In Proton-Nucleus Collisions, Kirill Tuchin Jan 2004

Heavy Quark Production By A Quasi-Classical Color Field In Proton-Nucleus Collisions, Kirill Tuchin

Kirill Tuchin

We calculate the inclusive heavy quark production cross section for proton-nucleus collisions at high energies. We perform calculation in a quasi-classical approximation (McLerran-Venugopalan model) neglecting all low-x evolution effects. The derived expression for the differential cross section can be applied for studying the heavy quark production in the central rapidity region at RHIC.


Extraction Of Jet Properties From Two Particle Azimuthal Correlations In Pp And Auau Collisions At [Square Root Of S Subscript Nn] = 200 Gev , Paul Constantin Jan 2004

Extraction Of Jet Properties From Two Particle Azimuthal Correlations In Pp And Auau Collisions At [Square Root Of S Subscript Nn] = 200 Gev , Paul Constantin

Retrospective Theses and Dissertations

Two particle azimuthal correlation functions measured in pp and AuAu collisions at sNN = 200 GeV at midrapidity with the central arms of the PHENIX detector are analyzed in order to extract the properties of hadronic jets produced in QCD vacuum and highly excited QCD media, like the jet shape parameters jT and kT, the jet conditional yields (number of associated hadrons per high pT trigger hadron) and the jet fragmentation function.;The analysis of pp data starts with the measurement of the vacuum fragmentation function from which the pT dependence of the mean fragmentation momentum fraction 〈z〉 is extracted. We ...


Theoretical Models Of Many-Quark Bound States , Richard Jeffrey Lloyd Jan 2003

Theoretical Models Of Many-Quark Bound States , Richard Jeffrey Lloyd

Retrospective Theses and Dissertations

The foundations of Many-Fermion Dynamics (MFD) are developed with special attention paid to a treatment of color and flavor degrees of freedom. From these ingredients a framework was developed to calculate the properties of many-fermion bound states. The quark implementation of MFD (MFDq) was extensively tested on the 2-body problem against the established nucleon implementation of MFD (MFDn). We were able to perform a limited set of self-consistency checks of MFDq in the 4-body problem to test a proper treatment of all computed matrix elements.;Finally, calculations are presented using MFDn to predict the properties of 4-body charmonium bound states ...


Statistical And Thermal Properties Of Mesoscopic Systems: Application To The Many-Nucleon System , Bassam A. Shehadeh Jan 2003

Statistical And Thermal Properties Of Mesoscopic Systems: Application To The Many-Nucleon System , Bassam A. Shehadeh

Retrospective Theses and Dissertations

The dissertation investigates the statistical and thermal properties of mesoscopic systems and applies it to the multi-nucleon systems. The investigation was carried out using four approaches starting from the simplest and progressing to the more sophisticated. The first approach develops and employs the three-dimensional simple harmonic oscillator (3D-SHO) quantum statistics to obtain the thermal properties of multi-particle systems. The recently discovered method that relates the single particle oscillator properties to the multi particle oscillator is applied. The approach is successful in predicting observables at temperatures beginning slightly above the ground state domain for nuclear systems. The 3D-SHO potential function is ...


Antiprotons And Other Nuclear Matters , Brett Steven Fadem Jan 2002

Antiprotons And Other Nuclear Matters , Brett Steven Fadem

Retrospective Theses and Dissertations

We present antiproton invariant multiplicities from Experiment 941 using 12 and 19 GeV/c proton beams incident upon targets of Pb, Cu and Be. Since we are currently unable to calculate antiproton yields in this regime from first principles, we must rely on empirical data in order to answer questions involving antibaryon production at these energies. Typically, the motivation for studying this topic using proton-nucleus (p-A) collisions is to shed light on antiproton production in the more complicated collisions between heavy nuclei (A-A). For this reason, this thesis will use the measured target dependence to illuminate issues relating to annihilation ...


Hadron Structures And Decays Within Quantum Chromodynamics , Alaa Abd El-Hady Jan 1998

Hadron Structures And Decays Within Quantum Chromodynamics , Alaa Abd El-Hady

Retrospective Theses and Dissertations

We have evaluated the meson spectrum using a relativistic model based on reductions of Bethe-Salpeter equation. We included one gluon exchange from Quantum Chromodynamics (QCD) and phenomenological confinement in the interaction kernel. We used an ansatz for the running of the coupling constant with the meson masses. We fitted more than forty states ranging from a hundred MeV to a few GeV using seven parameters, with root mean square deviation from experimental data of 40-50 MeV. This establishes our successful QCD-based model for many applications which we investigate;We employed our model to examine the strong interaction medium effects on ...


Ambiguities In The Definition Of Spin-Dependent Parton Distributions , Yuen-Wing Law Jan 1998

Ambiguities In The Definition Of Spin-Dependent Parton Distributions , Yuen-Wing Law

Retrospective Theses and Dissertations

We investigate the ambiguities in defining polarized parton distributions. We point out that in addition to the well-known renormalization scheme dependence in the unpolarized case, there are extra ambiguities in defining polarized parton distributions. These include the definition of [gamma]5 in d-dimension and interpretation of the anomalous contribution. Here, a new renormalization/factorization scheme called UV Subtraction (UVS) is proposed. In the new UVS scheme, it exploits the freedom in renormalization to eliminate the ambiguities arising from [gamma]5 and anomalous contribution. We also discuss the consequences of these ambiguities on the calculable short-distance partonic hard parts and corresponding ...


Direct Photon Production In A Nuclear Environment , Xiaofeng Guo Jan 1996

Direct Photon Production In A Nuclear Environment , Xiaofeng Guo

Retrospective Theses and Dissertations

The photon is a very good probe of short distance physics in strong interactions. It can be produced directly at short-distance or through fragmentation processes. Through one-loop order in perturbation theory of quantum chromodynamics (QCD), this thesis provides complete analytic expressions for both the inclusive and the isolated prompt photon production cross sections in hadronic final states of e+e- annihilations. It is the first time that the full angular dependence of the cross sections is derived. Extraction of photon fragmentation functions from e+e- annihilations is addressed. Using e+e-→[gamma]+X as an example, this work demonstrates for ...


Electromagnetic Dissociation Of Co And Au Targets By A 10.2 Gev/Nucleon Au Beam , Lars Albert Ewell Jan 1996

Electromagnetic Dissociation Of Co And Au Targets By A 10.2 Gev/Nucleon Au Beam , Lars Albert Ewell

Retrospective Theses and Dissertations

Collisions of relativistic heavy ions (RHI) can be broadly categorized as two types: central (nuclear force dominated) and peripheral (coulomb force dominated). The experiment described addresses the latter. Unlike the neutron removal cross section via the nuclear force [sigma]nucl, the neutron removal cross section via the coulomb force [sigma]coul is an increasing function of energy due to the Lorentz contraction of the electromagnetic fields. As more energetic and heavier (higher Z) RHI beams have become available, there appears to be an overestimation of the one neutron removal cross section by the virtual photon theoretical treatment of Wiezsacker, Williams ...


Qcd Near The Light Front , Thomas John Fields Jan 1996

Qcd Near The Light Front , Thomas John Fields

Retrospective Theses and Dissertations

In this thesis, we propose a set of techniques to study the non-perturbative behavior of quantum field theories. These techniques include the use of near light front coordinates and a theory of effective Hamiltonians;Our ultimate goal will be to apply these methods to quantum electrodynamics (QED) and quantum chromodynamics (QCD). As a first test we will investigate simplified versions of QED and QCD with these methods over all ranges or their coupling constants;First, we solve the Schwinger model, which is QED in one space and one time dimension. We use this test model in both the massless and ...


Relativistic Two-Body Wave Equations , Alan James Sommerer Jan 1993

Relativistic Two-Body Wave Equations , Alan James Sommerer

Retrospective Theses and Dissertations

The history and conceptual development of relativistic two-body formalisms leading up to the Bethe-Salpeter equation are reviewed. The various three dimensional reductions of the Bethe-Salpeter equation, in particular the quasipotential equations, and methods for solving them are discussed. Previous studies which attempted to assess the relative merits of the various equations are examined, and a new criterion for judging the equations is proposed. The bound state energy predictions of the traditional quasipotential equations are compared with the predictions of fourth order perturbation theory at small coupling. The equations are ranked according to how well they reproduce perturbation theory at low ...


High-Spin [Gamma]-Ray Spectroscopy In 198bi, Superdeformation In 191au, And Multi-Photon Resonances In Low Energy E+E- Scattering , Duc Ta Vo Jan 1993

High-Spin [Gamma]-Ray Spectroscopy In 198bi, Superdeformation In 191au, And Multi-Photon Resonances In Low Energy E+E- Scattering , Duc Ta Vo

Retrospective Theses and Dissertations

The properties of low-and high-spin levels in [superscript]198Bi have been studied with the [superscript]181Ta([superscript]22Ne,5n)[superscript]198Bi reaction at 116 MeV and 120 MeV bombarding energies. Levels along and near the yrast lines, including one isomer, were established up to spin J ≈ 30\hbar. The main configurations of these states are suggested to be [pi] h[subscript]9/2 coupled to the known excited states in [superscript]197Pb. A sequence of states built on the excitation of the odd proton (coupled to one, two, or three quasi neutron-holes) was observed. In addition, at least two collective ...


Applications Of The Bethe-Salpeter Equation In Nuclear Physics , John R. Spence Jan 1989

Applications Of The Bethe-Salpeter Equation In Nuclear Physics , John R. Spence

Retrospective Theses and Dissertations

This work reports the study of techniques for solving the Bethe-Salpeter equation with a confinement kernel and reports the foundation of a program for constructing a relativistic model of the hadrons based upon the Bethe-Salpeter equation. The techniques described here represent a solution of the problem of constructing a relativistic model for the mesons. General methods are given for defining a confinement kernel in momentum space, of transforming the confinement kernel into an integrodifferential operator, and for solving the integral equations which result from applying these procedures to the Bethe-Salpeter equation;Momentum space eigenfunctions for charmonium are obtained and found ...


Theory Of Inelastic Lepton-Nucleus Scattering , Granddon D. Yen Jan 1988

Theory Of Inelastic Lepton-Nucleus Scattering , Granddon D. Yen

Retrospective Theses and Dissertations

This work reports the studies of the quark structure of a nucleus. Deuterium is the simplest nuclear system with weak binding energy and low average density so that it provides an ideal starting point for this study. Models based on the one photon exchange process should provide a good description of deuterium inelastic lepton scattering data. Furthermore, the available deuterium data cover the widest kinematical range among all A ≥ 2 targets. If the conventional nuclear physics picture is correct, the quasi-elastic nucleon knockout process along with nucleon inelastic processes should be able to account for the inelastic lepton scattering data ...


Shell Model Studies Of The N=50 Isotones In The 78ni 'Doubly Magic' Region , Jeff Allen Winger Jan 1987

Shell Model Studies Of The N=50 Isotones In The 78ni 'Doubly Magic' Region , Jeff Allen Winger

Retrospective Theses and Dissertations

The study of excited states in the N = 50 isotones ('82)Ge and ('83)As following the (beta) decay of the neutron-rich nuclei ('82)Ga and ('83)Ge is reported. This work was performed using the on-line isotope separator facility TRISTAN at Brookhaven National Laboratory. The ('83)Ge half-life was measured to be 1.85 (+OR-) 0.06 s. On the basis of (gamma) singles and (gamma)-(gamma) coincidence measurements a total of 51 (gamma) rays were placed in a level scheme for ('83)As with 27 levels up to 4.84 MeV. The ('82)Ga half-life was measured to ...


Photon Statistics Of Light Resonantly Scattered From A Three-Level Atom , Rollin Michael Evans Jan 1984

Photon Statistics Of Light Resonantly Scattered From A Three-Level Atom , Rollin Michael Evans

Retrospective Theses and Dissertations

A laser spectroscopy system and the equipment needed for resonance-fluorescence studies with the photon-burst method in an extended interaction region were developed. To accommodate the long, variable transit times of thermal atoms across this extended region a resettable coincidence counter was used;The photon statistics of light scattered from the three-level 5535 A transition in barium were investigated. These statistics agreed well with theory developed in conjunction with this work. An atomic branching ratio of 375 (+OR-) 30 was obtained from the photon number distributions, establishing a new method for determining this quantity. The affect of radiation pressure upon the ...


Nonstrange Baryon Properties From One-Gluon Exchange And Linear Confinement Between Quarks , Mark Linden Kiefer Jan 1983

Nonstrange Baryon Properties From One-Gluon Exchange And Linear Confinement Between Quarks , Mark Linden Kiefer

Retrospective Theses and Dissertations

We present a model of the quark structure of nonstrange baryons. We use quasi-quarks whose masses are roughly 1/3 the proton mass and which interact via one-gluon exchange and linear confining two-body potentials. The model is semirelativistic in that the quark kinetic energies and the one-gluon exchange potential include the lowest order, nonrelativistic terms plus the first order relativistic corrections. The three quark Hamiltonian is diagonalized in a harmonic oscillator basis using all states up to 6(omega) of excitation energy. The basis states have the center of mass motion explicitly factored out and are overall antisymmetric in the ...


A Local Approximation Of A Qcd-Inspired Nucleon-Nucleon Interaction , Deborah Reed-Margetan Jan 1983

A Local Approximation Of A Qcd-Inspired Nucleon-Nucleon Interaction , Deborah Reed-Margetan

Retrospective Theses and Dissertations

There have been several attempts to understand the nature of the nucleon-nucleon interaction on the basis of the quark structure of the nucleon. In this work, the potential model approach is pursued. In particular, this project expands upon work done by P. D. Morley, D. L. Pursey, and S. A. Williams. They started with a basic interaction between quarks which was the sum of a phenomenological confining potential for quark confinement and a one-gluon-exchange potential inspired by QCD. This model led naturally to a nonlocal nucleon-nucleon interaction. In this thesis, a consistent local approximation to this nonlocal potential is presented ...


Coulomb Dissociation In Relativistic Heavy Ion Reactions , Mark T. Mercier Jan 1982

Coulomb Dissociation In Relativistic Heavy Ion Reactions , Mark T. Mercier

Retrospective Theses and Dissertations

Targets of ('12)C, ('59)Co, ('89)Y, ('197)Au and ('238)U were bombarded by 2.1 GeV/A ('1)H, ('12)C and ('20)Ne projectiles using the SuperHILAC and BEVATRON facilities at Lawrence Berkeley Laboratory (LBL). The beam flux was calculated by monitoring the decay of ('11)C produced from the ('12)C(projectile,projectile n)('11)C reaction. Residual gamma-ray activity from the Co, Y, Au and U targets was collected in order to trace the decay of several reaction products. The experiment focused on the calculation of cross sections for the formation of products with ...


Moment Methods With Effective Nuclear Hamiltonians: Calculation Of Radial Moments , Robert Hartman Belehrad Jan 1980

Moment Methods With Effective Nuclear Hamiltonians: Calculation Of Radial Moments , Robert Hartman Belehrad

Retrospective Theses and Dissertations

No abstract provided.


Comparison Between Phase Shift Derived And Exactly Calculated Nucleon-Nucleon Interaction Matrix Elements , Alan Wayne Gregersen Jan 1977

Comparison Between Phase Shift Derived And Exactly Calculated Nucleon-Nucleon Interaction Matrix Elements , Alan Wayne Gregersen

Retrospective Theses and Dissertations

No abstract provided.


Decay Schemes For Mass Separated 136i, And 138i, And 137xe , Warren Ralph Western Jan 1976

Decay Schemes For Mass Separated 136i, And 138i, And 137xe , Warren Ralph Western

Retrospective Theses and Dissertations

No abstract provided.


On-Line Gamma-Gamma Angular Correlation Studies Of Cascades In 140ba, 90sr, And 140cs , Larry James Alquist Jan 1975

On-Line Gamma-Gamma Angular Correlation Studies Of Cascades In 140ba, 90sr, And 140cs , Larry James Alquist

Retrospective Theses and Dissertations

No abstract provided.


Lifetimes Of Nuclear Levels In The Decays Of Some Mass-Separated Fission Products , James Albert Morman Jan 1974

Lifetimes Of Nuclear Levels In The Decays Of Some Mass-Separated Fission Products , James Albert Morman

Retrospective Theses and Dissertations

No abstract provided.


Gamma-Gamma Angular Correlation Studies Of Cascades In 138ba And 142ce , Gary John Basinger Jan 1974

Gamma-Gamma Angular Correlation Studies Of Cascades In 138ba And 142ce , Gary John Basinger

Retrospective Theses and Dissertations

No abstract provided.


A Systematic Study Of The Photo-Disintegration Of Germanium Isotopes , Jon Jay Mccarthy Jan 1973

A Systematic Study Of The Photo-Disintegration Of Germanium Isotopes , Jon Jay Mccarthy

Retrospective Theses and Dissertations

No abstract provided.


Identification And Characterization Of Isomeric States In The De-Excitation Of 252cf Fission Fragments , Ronald Gene Clark Jan 1972

Identification And Characterization Of Isomeric States In The De-Excitation Of 252cf Fission Fragments , Ronald Gene Clark

Retrospective Theses and Dissertations

No abstract provided.


Soluble Model Calculations Of The Continuum Structure Of Closed-Shell Nuclei In The Eigenchannel Reaction Theory , Gerald Francis Gieraltowski Jan 1971

Soluble Model Calculations Of The Continuum Structure Of Closed-Shell Nuclei In The Eigenchannel Reaction Theory , Gerald Francis Gieraltowski

Retrospective Theses and Dissertations

No abstract provided.