Elementary Particles and Fields and String Theory Commons^™

Perturbative Renormalization And Mixing Of Quark And Glue Energy-Momentum Tensors On The Lattice, Michael J. Glatzmaier, Keh-Fei Liu, Yi-Bo Yang

Physics and Astronomy Faculty Publications

We report the renormalization and mixing constants to one-loop order for the quark and gluon energy-momentum (EM) tensor operators on the lattice. A unique aspect of this mixing calculation is the definition of the glue EM tensor operator. The glue operator is comprised of gauge-field tensors constructed from the overlap Dirac operator. The resulting perturbative calculations are performed using methods similar to the Kawai approach using the Wilson fermion and gauge actions for all QCD vertices and the overlap Dirac operator to define the glue EM tensor. Our results are used to connect the lattice QCD results of quark and …

Crabbing System For An Electron-Ion Collider, Alejandro Castilla

Physics Theses & Dissertations

As high energy and nuclear physicists continue to push further the boundaries of knowledge using colliders, there is an imperative need, not only to increase the colliding beams’ energies, but also to improve the accuracy of the experiments, and to collect a large quantity of events with good statistical sensitivity. To achieve the latter, it is necessary to collect more data by increasing the rate at which these pro- cesses are being produced and detected in the machine. This rate of events depends directly on the machine’s luminosity. The luminosity itself is proportional to the frequency at which the beams …

Enhancing High-Order-Harmonic Generation By Time Delays Between Two-Color, Few-Cycle Pulses, Dian Peng, Liang-Wen Pi, M. V. Frolov, Anthony F. Starace

Anthony F. Starace Publications

Use of time delays in high-order-harmonic generation (HHG) driven by intense two-color, few-cycle pulses is investigated in order to determine means of optimizing HHG intensities and plateau cutoff energies. Based upon numerical solutions of the time-dependent Schrõdinger equation for the H atom as well as analytical analyses, we show that introducing a time delay between the two-color, few-cycle pulses can result in an enhancement of the intensity of the HHG spectrum by an order of magnitude (or more) at the cost of a reduction in the HHG plateau cutoff energy. Results for both positive and negative time delays as well …

Glue Spin And Helicity In The Proton From Lattice Qcd, Yi-Bo Yang, Raza Sabbir Sufian, Andrei Alexandru, Terrence Draper, Michael J. Glatzmaier, Keh-Fei Liu, Yong Zhao

Physics and Astronomy Faculty Publications

We report the first lattice QCD calculation of the glue spin in the nucleon. The lattice calculation is carried out with valence overlap fermions on 2 + 1 flavor domain-wall fermion gauge configurations on four lattice spacings and four volumes including an ensemble with physical values for the quark masses. The glue spin SG in the Coulomb gauge in the modified minimal subtraction (MS¯) scheme is obtained with one-loop perturbative matching. We find the results fairly insensitive to lattice spacing and quark masses. We also find that the proton momentum dependence of S_G in the range 0 ≤ |p …

Pion Distribution Amplitude And Quasidistributions, A. V. Radyushkin

Physics Faculty Publications

We extend our analysis of quasidistributions onto the pion distribution amplitude. Using the formalism of parton virtuality distribution amplitudes, we establish a connection between the pion transverse momentum dependent distribution amplitude Ψ(x, k²_⊥) and the pion quasidistribution amplitude (QDA) Q_π(y, p₃). We build models for the QDAs from the virtuality-distribution-amplitude-based models for soft transverse momentum dependent distribution amplitudes, and analyze the p₃ dependence of the resulting QDAs. As there are many models claimed to describe the primordial shape of the pion distribution amplitude, we present the p₃-evolution …

Particle Physics Model For The 17 Mev Anomaly In Beryllium Nuclear Decays, Jonathan L. Feng, Bartosz Fornal, Iftah Galon, Susan Gardner, Jordan Smolinsky, Tim M. P. Tait, Philip Tanedo

Physics and Astronomy Faculty Publications

The 6.8σ anomaly in excited ⁸Be nuclear decays via internal pair creation is fit well by a new particle interpretation. In a previous analysis, we showed that a 17 MeV protophobic gauge boson provides a particle physics explanation of the anomaly consistent with all existing constraints. Here we begin with a review of the physics of internal pair creation in ⁸Be decays and the characteristics of the observed anomaly. To develop its particle interpretation, we provide an effective operator analysis for excited ⁸Be decays to particles with a variety of spins and parities and show that …

Line Tension And Its Influence On Droplets And Particles At Surfaces, Bruce M. Law, Sean P. Mcbride, Jiang Yong Wang, Haeng Sub Wi, Govind Paneru, Santigo Betelu, Baku Ushijima, Youichi Takata, Bret Flanders, Fernando Bresme, Hiroki Matsubara, Takanori Takiue, Makoto Aratono

Physics Faculty Research

In this review we examine the influence of the line tension s on droplets and particles at surfaces. The line tension influences the nucleation behavior and contact angle of liquid droplets at both liquid and solid surfaces and alters the attachment energetics of solid particles to liquid surfaces. Many factors, occurring over a wide range of length scales, contribute to the line tension. On atomic scales, atomic rearrangements and reorientations of submolecular components give rise to an atomic line tension contribution satom (1 nN), which depends on the similarity/dissimilarity of the droplet/particle surface composition compared with the surface upon which …

Harmonically Resonant Cavity As A Bunch Length Monitor, B. Roberts, M. Pablo, E. Forman, J. Grames, F. Hannon, R.Kazimi W. Moore, M. M. Ali

Physics Faculty Publications

A compact, harmonically-resonant cavity with a fundamental resonant frequency of 1497 MHz was used to evaluate the temporal characteristics of electron bunches produced by a 130 kV dc high voltage spin-polarized photoelectron source at the Continuous Beam Accelerator Facility (CEBAF) photoinjector, delivered at 249.5 and 499 MHz repetition rates and ranging in width from 45 to 150 picoseconds (FWHM). The cavity’s antenna was attached directly to a sampling oscilloscope that detected the electron bunches as they passed through the cavity bore with a sensitivity of ~ mV/ μA. The oscilloscope wave-forms are a superposition of the harmonic modes excited by …

Locality And Efficient Evaluation Of Lattice Composite Fields: Overlap-Based Gauge Operators, Andrei Alexandru, Ivan Horváth

Physics and Astronomy Faculty Publications

We propose a novel general approach to locality of lattice composite fields, which in case of QCD involves locality in both quark and gauge degrees of freedom. The method is applied to gauge operators based on the overlap Dirac matrix elements, showing for the first time their local nature on realistic path-integral backgrounds. The framework entails a method for efficient evaluation of such nonultralocal operators, whose computational cost is volume independent at fixed accuracy, and only grows logarithmically as this accuracy approaches zero. This makes computation of useful operators, such as overlap-based topological density, practical. The key notion underlying these …

Data Collection And Analysis At The Atlas Detector, Savannah Thais

Yale Day of Data

No abstract provided.

Supergroups In Critical Dimensions And Division Algebras, Čestmir Burdik, Sultan Catto, Yasemin Gürcan, Amish Khalfan, Levent Kurt, V. Kato La

Publications and Research

We establish a link between classical heterotic strings and the groups of the magic square associated with Jordan algebras, allowing for a uniform treatment of the bosonic and superstring sectors of the heterotic string.

Commissioning Of The Large Angle Beamstrahlung Monitor At Superkekb, Salvatore Di Carlo

Wayne State University Dissertations

The Large Angle Beamstrahlung Monitor (LABM) is a device capable to monitor

the beam-beam collisions. The LABM measures the beamstrahlung light emitted

at large angle during the collisions of electron and positron beams. The properties

of the beamstrahlung, spectrum and polarization, are fundamentally related to the

size and relative position of the beams. Measuring the beamstrahlung, the LABM

delivers information about the size of the beams and their relative position at the

interaction point. The LABM will be part of the instrumentation of SuperKEKB,

a new e+e− collider that aims to reach the world record luminosity of 8×10^35 cm^-2 s^-1. …

Azimuthally-Differential Pion Femtoscopy Relative To The Second And Third Harmonic In Pb-Pb Collisions, Mohammad Saleh

Wayne State University Dissertations

Heavy-ion collisions at LHC energies create a hot and dense medium of deconned quarks

and gluons, known as the quark-gluon plasma (QGP) [56]. The QGP reball rst expands,

cools and then freezes out into a collection of nal-state hadrons. Correlations between the

free particles carry information about the space-time extent of the emitting source, and are

imprinted on the nal-state spectra due to a quantum-mechanical interference eect [18].

The correlation of two identical particles at small relative momentum, commonly known as

intensity, or Hanbury Brown-Twiss (HBT), interferometry, is an eective tool to study the

space-time structure of the emitting source …

Design Of A High Luminosity 100 Tev Proton Antiproton Collider, Sandra Jimena Oliveros Tautiva

Electronic Theses and Dissertations

Currently new physics is being explored with the Large Hadron Collider at CERN and with Intensity Frontier programs at Fermilab and KEK. The energy scale for new physics is known to be in the multi-TeV range, signaling the need for a future collider which well surpasses this energy scale. A 10 34 cm-2 s-1 luminosity 100 TeV proton-antiproton collider is explored with 7× the energy of the LHC. The dipoles are 4.5 T to reduce cost. A proton-antiproton collider is selected as a future machine for several reasons. The cross section for many high mass states is 10 times higher …

Final Muon Cooling For A Muon Collider, John Gabriel Acosta Castillo

Electronic Theses and Dissertations

To explore the new energy frontier, a new generation of particle accelerators is needed. Muon colliders are a promising alternative if muon cooling can be made to work. Muons are 200 times heavier than electrons, so they produce less synchrotron radiation, and they behave like point particles. However, they have a short lifetime of 2.2 μs and the beam is more difficult to cool than an electron beam. The Muon Accelerator Program (MAP) was created to develop concepts and technologies required by a muon collider. An important effort has been made in the program to design and optimize a muon …

Neutron Decay Correlations In The Nab Experiment, L. J. Broussard, R. Alarcon, S. Baeßler, L. Barrón Palos, N. Birge, T. Bode, J. D. Bowman, T. Brunst, J. R. Calarco, J. Caylor, T. Chupp, V. Cianciolo, Christopher Crawford, G. W. Dodson, J. Dubois, W. Fan, W. Farrar, N. Fomin, E. Frlež, J. Fry, M. T. Gericke, F. Glück, G. L. Greene, R. K. Grzywacz, V. Gudkov, C. Hendrus, F. W. Hersman, T. Ito, H. Li, N. Macsai, Bradley R. Plaster, Aaron P. Sprow

Physics and Astronomy Faculty Publications

The Nab experiment will measure the correlation a between the momenta of the beta particle and antineutrino in neutron decay as well as the Fierz term b which distorts the beta spectrum.

Bulk Viscous Corrections To Screening And Damping In Qcd At High Temperatures, Qianqian Du, Adrian Dumitru, Yun Guo, Michael Strickland

Publications and Research

Non-equilibrium corrections to the distribution functions of quarks and gluons in a hot and dense QCD medium modify the “hard thermal loops” (HTL). The HTLs determine the retarded, advanced, and symmetric (time-ordered) propagators for gluons with soft momenta as well as the Debye screening and Landau damping mass scales. We compute such corrections to a thermal as well as to a non-thermal fixed point. The screening and damping mass scales are sensitive to the bulk pressure and hence to (pseudo-) critical dynamical scaling of the bulk viscosity in the vicinity of a second-order critical point. This could be reflected in …

Unification Of Gravity And Quantum Theory, Adam Daniels

Faculty-Sponsored Student Research & Capstones

An overview of the four fundamental forces of physics as described by the Standard Model (SM) and prevalent unifying theories beyond it is provided. Background knowledge of the particles governing the fundamental forces is provided, as it will be useful in understanding the way in which the unification efforts of particle physics has evolved, either from the SM, or apart from it. It is shown that efforts to provide a quantum theory of gravity have allowed supersymmetry (SUSY) and M-Theory to become two of the prevailing theories for unifying gravity with the remaining non-gravitational forces.

Determination Of The Proton Spin Structure Functions For 0.05 < Q2 <5gev2 Using Clas, R. G. Fersch, N. Guler, P. Bosted, A. Deur, K. Griffioen, C. Keith, S E. Kuhn, R. Minehart, Y. Prok, K. P. Adhikari, S. Bültmann, S. Careccia, Gail Dodge, V. G. Lagerquist, L. B. Weinstein

Physics Faculty Publications

We present the results of our final analysis of the full data set of g^p₁ Q², the spin structure function of the proton, collected using CLAS at Jefferson Laboratory in 2000-2001. Polarized electrons with energies of 1.6, 2.5, 4.2, and 5.7 GeV were scattered from proton targets ¹⁵NH₃ dynamically polarized along the beam direction) and detected with CLAS. From the measured double spin asymmetries, we extracted virtual photon asymmetries A^p₁ and A^p₂ and spin structure functions g ^p₁ and g^p₂ over a wide kinematic range (0.05 GeV …

Nonperturbative Evolution Of Parton Quasi-Distributions, A. V. Radyushkin

Physics Faculty Publications

Using the formalism of parton virtuality distribution functions (VDFs) we establish a connection between the transverse momentum dependent distributions (TMDs) F(x,k²_⊥) and quasi-distributions (PQDs) Q(y,p₃) introduced recently by X. Ji for lattice QCD extraction of parton distributions f(x). We build models for PQDs from the VDF-based models for soft TMDs, and analyze the p₃ dependence of the resulting PQDs. We observe a strong nonperturbative evolution of PQDs for small and moderately large values of p₃ reflecting the transverse momentum dependence of TMDs. Thus, the study of PQDs on the lattice …