PaperPanorama

Nuclear Theory·nucl-th

Thursday·May 7, 2015

8 papers4 primary·4 cross-listed

  1. 06

    Calculating TMDs of a Large Nucleus: Quasi-Classical Approximation and Quantum Evolution

    Yuri V. Kovchegov🇺🇸 · Matthew D. Sievert🇺🇸

    We set up a formalism for calculating transverse-momentum-dependent parton distribution functions (TMDs) using the tools of saturation physics. By generalizing the quasi-classical Glauber-Gribov-Mueller/McLerran-Venugopalan approximation to allow for the possibility of spin-orbit coupling, we show how any TMD can be calculated in the saturation framework. This can also be applied to the TMDs of a proton by modeling it as a large "nucleus." To illustrate our technique, we calculate the quark TMDs of an unpolarized nucleus at large-x: the unpolarized quark distribution and the quark Boer-Mulders distribution. We observe that spin-orbit coupling leads to mixing between different TMDs of the nucleus and of the nucleons. We then consider the evolution of TMDs: at large-x, in the double-logarithmic approximation, we obtain the Sudakov form factor. At small-x the evolution of unpolarized-target quark TMDs is governed by BK/JIMWLK evolution, while the small-x evolution of polarized-target quark TMDs appears to be dominated by the QCD Reggeon.

    hep-phnucl-thNPB(2016)·61 citations
  2. 07

    Thermalization of Quark-Gluon Plasma in Magnetic Field at Strong Coupling

    Kiminad A. Mamo🇺🇸 · Ho-Ung Yee🇺🇸

    We study thermalization of strongly coupled gauge theory plasma in the presence of magnetic field using the AdS/CFT correspondence. We utilize the falling energy-shell model as a holographic description of gauge theory plasma undergoing thermalization, and find the effect of magnetic field on thermalization time in various space-time dimensions. Our results demonstrate that magnetic field universally hastens thermalization of strongly coupled gauge theory plasma.

    hep-phhep-thnucl-thPRD(2015)·14 citations
  3. 08

    Excitation function of elastic scattering from a unitarily extended Bialas-Bzdak model

    F. Nemes🇨🇭 · T. Csörgő🇭🇺 · M. Csanád🇭🇺

    The Bialas-Bzdak model of elastic proton-proton scattering assumes a purely imaginary forward scattering amplitude, which consequently vanishes at the diffractive minima. We extended the model to arbitrarily large real parts in a way that constraints from unitarity are satisfied. The resulting model is able to describe elastic scattering not only at the lower ISR energies but also at 7~TeV in a statistically acceptable manner, both in the diffractive cone and in the region of the first diffractive minimum. The total cross-section as well as the differential cross-section of elastic proton-proton scattering is predicted for the future LHC energies of 13, 14, 15~TeV and also to 28~TeV. A non-trivial, significantly non-exponential feature of the differential cross-section of elastic proton-proton scattering is analyzed and the excitation function of the non-exponential behavior is predicted. The excitation function of the shadow profiles is discussed and related to saturation at small impact parameters.

    hep-phnucl-thInt.J.Mod.Phys.A(2015)·33 citations

Affiliations

first authorsco-authorsvia INSPIRE