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We derive the generalized chiral kinetic equations which are applicable to the fermions with arbitrary mass. We show how the dynamical magnetic-moment distribution function could lead to spin polarization and electric charge separation. We…

High Energy Physics - Phenomenology · Physics 2023-08-16 Shu-Xiang Ma , Jian-Hua Gao

A forward dispersion calculation is implemented for the spin polarizabilities $\gamma_1, ... ,\gamma_4$ of the proton and the neutron. These polarizabilities are related to the spin structure of the nucleon at low energies and are…

Nuclear Theory · Physics 2009-10-30 D. Drechsel , G. Krein , O. Hanstein

We compute the strong coupling constant $G_{B^{**} B \pi} \; (G_{D^{**} D \pi})$, where $B^{**}$ ($D^{**}$) is the $0^+$ $P-$wave $b \bar q \; (c \bar q)$ state, by QCD sum rules and by light-cone sum rules. The two methods give compatible…

High Energy Physics - Phenomenology · Physics 2009-10-28 P. Colangelo , F. De Fazio , N. Di Bartolomeo , R. Gatto , G. Nardulli

We propose a novel method to determine the strong coupling of quantum chromodynamics (QCD) and fix its running behavior at all scales by using the Bjorken sum rules (BSR). The BSR defines an effective coupling $\alpha^{g_1}_s(Q)$ which…

High Energy Physics - Phenomenology · Physics 2025-01-28 Qing Yu , Xing-Gang Wu , Hua Zhou , Jian-Ming Shen

We review the theory and present status of the proton spin problem with emphasis on possible gluonic and sea contributions. We discuss the possibility of a J=1 fixed pole correction to the Ellis-Jaffe sum rule for polarized deep inelastic…

High Energy Physics - Phenomenology · Physics 2007-05-23 Steven D. Bass

We present approximations of varying degree of sophistication to the integral equations for the (gluon) structure functions of a hadron (``the partonic flux factor'') in a model valid in the Leading Log Approximation with a running coupling…

High Energy Physics - Phenomenology · Physics 2009-10-30 B. Andersson , G. Gustafson , H. Kharraziha

The spin polarization measurements of particles emitted in heavy-ion collisions have opened the possibility for new phenomenological investigations of spin physics in relativistic fluids. The theoretical predictions of global polarization…

Nuclear Theory · Physics 2022-12-13 M. Buzzegoli , F. Becattini , G. Inghirami , I. Karpenko , A. Palermo

Evolution of spin polarization in the presence of external electric field is studied for collision energies $\sqrt{s_{\rm NN}}=27\,{\rm GeV}$ and $\sqrt{s_{\rm NN}}=200\,{\rm GeV}$. The numerical analysis is done in the perfect-fluid…

High Energy Physics - Phenomenology · Physics 2021-06-02 Rajeev Singh , Masoud Shokri , Radoslaw Ryblewski

Relativistic hydrodynamics has been quite successful in describing the properties of strongly-interacting matter produced in heavy-ion collision experiments. Recently, there has been a significant advancement in this field to explain the…

High Energy Physics - Phenomenology · Physics 2023-10-03 Rajeev Singh

We briefly review a recently proposed formalism of perfect-fluid hydrodynamics with spin, which is a generalization of the standard hydrodynamic framework and provides a natural tool for describing the evolution of spin-polarized systems of…

High Energy Physics - Phenomenology · Physics 2020-11-05 Rajeev Singh

A BCS-like variational wave-function, which is exact in the infinite field limit, is used to study the interplay among Zeeman energies, lateral confinement and particle correlations induced by the Coulomb interactions in strongly pumped…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 Boris A. Rodriguez , Augusto Gonzalez

We show that it is possible to define a Lorentz-covariant reduced spin density matrix for massive particles. Such a matrix allows one to calculate the mean values of observables connected with spin measurements (average polarizations).…

Quantum Physics · Physics 2007-05-23 P. Caban , J. Rembielinski

In this talk, I will concentrate on $Q^2$-dependence of deep inelastic sum rules. I will first give a modern definition of deep-inelastic sum rules and then discuss physical origins of their scaling violation at finite $Q^2$. Following…

High Energy Physics - Phenomenology · Physics 2007-05-23 Xiangdong Ji

We introduce a distinctive feature of spin-polarized transport, the Spin Coulomb Drag: there is an intrinsic source of friction for spin currents due to the Coulomb interaction between spin ``up'' and spin ``down'' electrons. We calculate…

Strongly Correlated Electrons · Physics 2007-05-23 Irene D'Amico , Giovanni Vignale

The plasma consisting of confining gluons resulting from the Gribov quantization of the SU(3) Yang-Mills theory is studied using non-equilibrium fluid dynamical framework. Exploiting the Bjorken symmetry and using linear response theory a…

High Energy Physics - Phenomenology · Physics 2016-11-23 Wojciech Florkowski , Radoslaw Ryblewski , Nan Su , Konrad Tywoniuk

We study the polarized Bjorken sum rule at low momentum transfers in the range $0.22<Q<1.73 {\rm GeV}$ with the four-loop N$^3$LO expression for the coefficient function $C_{\rm Bj}(\alpha_s)$ in the framework of the common QCD perturbation…

High Energy Physics - Phenomenology · Physics 2015-05-28 V. L. Khandramai , R. S. Pasechnik , D. V. Shirkov , O. P. Solovtsova , O. V. Teryaev

The elastic contribution to the first moment of $g_2(x,Q^2)$ is analysed using a Drell-Yan-West type of relation and is shown to be negative. For a qualitative estimate the one-loop contributions to the polarized DIS sum rules in QED are…

High Energy Physics - Phenomenology · Physics 2009-10-30 I. V. Musatov , O. V. Teryaev , A. Schäfer

The spin-polarized homogeneous electron gas with densities $\rho_\uparrow$ and $\rho_\downarrow$ for electrons with spin `up' ($\uparrow$) and spin `down' ($\downarrow$), respectively, is systematically analyzed with respect to its…

Strongly Correlated Electrons · Physics 2009-11-10 P. Ziesche , F. Tasnadi

The generalized Baldin sum rule for virtual photon scattering, the unpolarized analogy of the generalized Gerasimov-Drell-Hearn integral, provides an important way to investigate the transition between perturbative QCD and hadronic…

Nuclear Experiment · Physics 2014-11-18 Y. Liang , M. E. Christy , R. Ent , C. E. Keppel

Charge sum rules for quark fragmentation functions are studied. The simultaneous implementation of the conservation of electric and baryon charges, strangeness and isospin symmetry is achieved when the fragmentation to both mesons and…

High Energy Physics - Phenomenology · Physics 2025-09-24 D. Kotlorz , O. V. Teryaev