A5076172588- High-Energy Particle Collisions Research
- Quantum Chromodynamics and Particle Interactions
- Particle physics theoretical and experimental studies
- Black Holes and Theoretical Physics
- Cosmology and Gravitation Theories
- Superconducting Materials and Applications
- Geophysics and Gravity Measurements
- Seismic Imaging and Inversion Techniques
- High-pressure geophysics and materials
- Quantum Mechanics and Applications
- Theoretical and Computational Physics
- Astrophysical Phenomena and Observations
- Granular flow and fluidized beds
- Geophysical Methods and Applications
- Spectroscopy and Quantum Chemical Studies
- Nanopore and Nanochannel Transport Studies
- Ionosphere and magnetosphere dynamics
- Dark Matter and Cosmic Phenomena
- Particle Accelerators and Free-Electron Lasers
- Particle accelerators and beam dynamics
- Quantum optics and atomic interactions
- Radiation Detection and Scintillator Technologies
- Microwave Imaging and Scattering Analysis
- Atomic and Subatomic Physics Research
- Characterization and Applications of Magnetic Nanoparticles
The Ohio State University
2016-2025
Pennsylvania State University
2017-2018
Los Alamos National Laboratory
2017-2018
Brookhaven National Laboratory
2000-2016
State Library of Ohio
2015-2016
University of Washington
2001-2005
Tel Aviv University
2001
University of Minnesota
1999-2000
European Organization for Nuclear Research
2000
University of Minnesota System
2000
We derive an equation determining the small-$x$ evolution of ${F}_{2}$ structure function a large nucleus which includes all multiple Pomeron exchanges in leading logarithmic approximation using Mueller's dipole model. show that double limit this reduces to Gribov-Levin-Ryskin equation.
We analyze the evolution equation describing all multiple hard Pomeron exchanges in hadronic or nuclear structure functions that was proposed earlier Phys. Rev. D 60, 034008 (1999). construct a perturbation series providing us with an exact solution to outside of saturation region. The demonstrates how at moderately high energies corrections single BFKL exchange contribution, which are due exchanges, start unitarizing total deep inelastic scattering cross section. show as energy increases...
We consider a very large ultrarelativistic nucleus. Assuming simple model of the nucleus and weak coupling we find classical solution for gluon field construct two-dimensional color charge density McLerran-Venugopalan out it. prove that states distribution, as function density, is Gaussian, confirming assumption made by McLerran Venugopalan.
We review the predictions of theory Color Glass Condensate for gluon production cross section in p(d)A collisions. demonstrate that at moderate energies, when can be calculated framework McLerran-Venugopalan model, it has only partonic level Cronin effect it. At higher energies/rapidities corresponding to smaller values Bjorken x quantum evolution becomes important. The is introduce suppression high-p_T gluons slightly decreasing enhancement. still leads produced all p_T.
We calculate the cross section of a single inclusive gluon production in deep inelastic scattering at very high energies saturation regime, where parton densities inside hadrons and nuclei are large evolution structure functions with energy is nonlinear. The expression we obtain for generated by this nonlinear evolution. analyze rapidity distribution produced gluons as well their transverse momentum spectrum given derived section. propose an ansatz multiplicity nuclear collisions which...
We calculate gluon production in deep inelastic scattering of the current j= - (1/4) F_{\mu\nu}^a off a large nucleus and nucleon-nucleus collisions. In covariant gauge calculation transverse momentum spectrum is determined by final state interactions with nucleons nucleus. light-cone are absent these effects come from wavefunction work an approximation which neglects QCD evolution gluons nucleon, that quasi-classical approximation.
We perform a quantitative analysis of the nuclear modification factor in deuteron--gold collisions R(dAu) within Color Glass Condensate approach, and compare our results with recent data from RHIC experiments. Our model leads to Cronin enhancement at mid-rapidity, while forward rapidities it predicts strong suppression all pT due low-x evolution. demonstrate that are consistent for dAu charged hadron spectra, R(CP) recently reported interval eta=0--3.2 by BRAHMS experiment RHIC. also make...
We consider the McLerran-Venugopalan model for calculation of small-$x$ part gluon distribution function a very large ultrarelativistic nucleus at weak coupling. construct Feynman diagrams which correspond to classical Weizs\"acker-Williams field found previously [Yu. V. Kovchegov, Phys. Rev. D 54, 5463 (1996)] as solution equations motion in light-cone gauge. Analyzing these we obtain limit model. show that long this is not violated can be used scattering amplitudes.
We study the solution of nonlinear Balitsky-Kovchegov evolution equation with recently calculated running coupling corrections [I. I. Balitsky, Phys. Rev. D 75, 014001 (2007). and Y. Kovchegov H. Weigert, Nucl. A784, 188 (2007).]. Performing a numerical we confirm earlier result Albacete et al. [Phys. 71, 014003 (2005).] (obtained by exploring several possible scales for coupling) that high energy leads to universal scaling behavior dipole-nucleus scattering amplitude, which is independent...
This White Paper presents the science case of an Electron-Ion Collider (EIC), focused on structure and interactions gluon-dominated matter, with intent to articulate it broader nuclear community. It was commissioned by managements Brookhaven National Laboratory (BNL) Thomas Jefferson Accelerator Facility (JLab) objective presenting a summary scientific opportunities goals EIC as follow-up 2007 NSAC Long Range plan. document is culmination community-wide effort in following series workshops...
Time and again, spin has been a key element in the exploration of fundamental physics. Spin-dependent observables have often revealed deficits assumed theoretical framework led to novel developments concepts. Spin is exploited many parity-violating experiments searching for physics beyond Standard Model or studying nature nucleon-nucleon forces. The RHIC program plays special role this grand scheme: it uses study how complex many-body system such as proton arises from dynamics QCD. Many...
We construct small-x evolution equations which can be used to calculate quark and anti-quark helicity TMDs PDFs, along with the g 1 structure function. These resum powers of α s ln2(1/x) in polarization-dependent ln(1/x) unpolarized includes saturation effects. The are written an operator form terms Wilson line-like operators. While do not close general, they become closed self-contained systems non-linear large-N c & N f limits. As a cross-check, ladder approximation, our map onto same...
We revisit the problem of small Bjorken-$x$ evolution gluon and flavor-singlet quark helicity distributions in shock wave ($s$-channel) formalism. Earlier works on subject same framework resulted an equation for field-strength $F^{12}$ "axial current" ${\bar\psi}\gamma^+\gamma^5\psi$ operators (sandwiched between appropriate light-cone Wilson lines) double-logarithmic approximation (DLA: summing powers $\alpha_s\,\ln^2(1/x)$ with $\alpha_s$ strong coupling constant). In this work, we observe...
The classical Yang-Mills equations are solved perturbatively in covariant gauge for a collision of two ultrarelativistic nuclei. nuclei taken as ensembles color charges on eikonal trajectories. gluon field is computed coordinate space up to cubic order the coupling constant $g$. We construct Feynman diagrams corresponding this and show equivalence diagrammatic approaches. An argument given which demonstrates that at higher orders $g$ description process breaks down. As an application, we...
We calculate production cross sections of a forward quark-gluon pair and two gluons at midrapidity in deep inelastic scattering high energy proton-nucleus collisions. The calculation is performed the framework color glass condensate formalism. first quasiclassical approximation, which includes multiple rescatterings target. then proceed to include effects nonlinear small-$x$ evolution sections. It interesting note that our result for two-gluon section appears be direct violation...
We determine the small-$x$ asymptotics of gluon helicity distribution in a proton at leading order perturbative QCD large $N_c$. To achieve this, we begin by evaluating dipole TMD small $x$. In process obtain an interesting new result: contrast to unpolarized case, operator governing behavior is different from corresponding polarized scattering amplitude (used our previous work quark distribution). then construct and solve novel large-$N_c$ evolution equations for related TMD. Our main...
We extend our earlier results for the quark helicity evolution at small $x$ [J. High Energy Phys. 01 (2016) 072] to derive small-$x$ asymptotics of flavor singlet and nonsinglet TMDs PDFs ${g}_{1}$ structure function. In case we rederive equations obtained in previous paper on subject 072], performing additional cross-checks results. construct new by employing large-${N}_{c}$ limit. All resum double-logarithmic powers ${\ensuremath{\alpha}}_{s}{\mathrm{ln}}^{2}(1/x)$ polarization-dependent...
We rederive the small-$x$ evolution equations governing quark helicity distribution in a proton using solely an operator-based approach. In our previous works on subject, were derived mix of diagrammatic and methods. this work, we double-logarithmic for terms ``polarized Wilson lines,'' operators consisting light-cone lines with one or two noneikonal local operator insertions which bring dependence. For first time give explicit complete expressions gluon polarized line operators, including...
We construct a numerical solution of the small-$x$ evolution equations recently derived in \cite{Kovchegov:2015pbl} for (anti)quark helicity TMDs and PDFs as well $g_1$ structure function. focus on case large $N_c$ where one finds closed set equations. Employing extracted intercept, we are able to predict directly from theory behavior at small $x$, which should have important phenomenological consequences. also give an estimate how much proton's spin may be $x$ what impact this has so-called...