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Related papers: Spin, Isospin and Strong Interaction Dynamics

200 papers

Recent developments and open issues in chiral dynamics with strange quarks are reviewed. Topics include: Order parameters of chiral symmetry breaking, the flavor dependence of these order parameters, speculations about the phase structure…

High Energy Physics - Phenomenology · Physics 2014-11-17 Ulf-G. Meißner

Within a chiral quark sigma model in which quarks interact via the exchange of sigma and pi-mesons, hadron properties are investigated. This model of the nucleon and delta is based on the idea that strong QCD forces on very short distances…

General Physics · Physics 2011-10-20 M. Rashdan , T. Ali , S. El-Kholy , M. Abu-Shady

The spin structure of the nucleon is analyzed in the framework of a Lorentz-invariant formulation of baryon chiral perturbation theory. The structure functions of doubly virtual Compton scattering are calculated to one-loop accuracy (fourth…

High Energy Physics - Phenomenology · Physics 2009-11-07 Véronique Bernard , Thomas R. Hemmert , Ulf-G. Meißner

The Weyl-Wigner formalism for evaluating the intrinsic information of Dirac bispinors as correlated qubits (localized) in a magnetic field is investigated in the extension to statistical ensembles. The confining external field quantizes the…

Quantum Physics · Physics 2024-02-01 C. F. Silva , A. E. Bernardini

I begin with a general discussion about importance of constructing a picture of the nucleon in terms of QCD degrees of freedom, emphasizing the role of spin structure functions. I then give a short overview on the theoretical and…

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

We apply the principles of discrete time mechanics discussed in earlier papers to the first and second quantised Dirac equation. We use the Schwinger action principle to find the anticommutation relations of the Dirac field and of the…

High Energy Physics - Theory · Physics 2008-11-26 Keith Norton , George Jaroszkiewicz

The "spin-up" and "spin-down" projections of the second order, chiral form of Dirac Theory are shown to fit a superposition of forms predicted in an earlier classical, complex scalar gauge theory (April, 1992 Class. Quantum Grav.). In some…

General Relativity and Quantum Cosmology · Physics 2017-06-30 J. E. Rankin

We present a method of simulating the Dirac equation in 3+1 dimensions for a free spin-1/2 particle in a single trapped ion. The Dirac bispinor is represented by four ionic internal states, and position and momentum of the Dirac particle…

Quantum Physics · Physics 2008-11-26 L. Lamata , J. Leon , T. Schaetz , E. Solano

Strongly interacting spins underlie many intriguing phenomena and applications ranging from magnetism to quantum information processing. Interacting spins combined with motion display exotic spin transport phenomena, such as superfluidity…

It is shown that single and double spin asymmetries in polarized diffractive $Q \bar Q$ production depend strongly on the spin structure of the quark-pomeron vertex. They can be studied in future spin experiments at HERA.

High Energy Physics - Phenomenology · Physics 2008-02-03 S. V. Goloskokov

The production, dynamic evolution, and decay of $\Delta$ particles play a crucial role in understanding the properties of high baryon density nuclear matter in intermediate-energy heavy-ion collisions. In this work, the energy-, density-,…

Nuclear Theory · Physics 2025-09-16 Manzi Nan , Pengcheng Li , Wei Zuo , Qingfeng Li

We revisit the scale evolution of the quark and gluon spin contributions to the proton spin, $\frac{1}{2}\Delta \Sigma$ and $\Delta G$, using the three-loop results for the spin-dependent evolution kernels available in the literature. We…

High Energy Physics - Phenomenology · Physics 2019-03-13 Daniel de Florian , Werner Vogelsang

We study the algebraic structure of the one-dimensional Dirac oscillator by extending the concept of spin symmetry to a noncommutative case. An SO(4) algebra is found connecting the eigenstates of the Dirac oscillator, in which the two…

Quantum Physics · Physics 2020-04-29 Wen-Ya Song , Fu-Lin Zhang

Some nonperturbative aspects of spin studies at RHIC are discussed and the predictions for single- and two-spin asymmetries are given. Among them are those which emphasize the role of angular orbital momentum in the spin structure of the…

High Energy Physics - Phenomenology · Physics 2007-05-23 Sergey Troshin , Nikolai Tyurin

The spin structure of the proton is investigated in the framework of an extended quark potential model which in addition to the conventional $3q$--structure also takes into account $(3q)(q\bar q)$--admixtures in the proton wave function.…

High Energy Physics - Phenomenology · Physics 2009-10-28 J. Keppler , H. M. Hofmann

It is by now well understood that spin asymmetry in deep inelastic scattering (DIS) can appear if two things are both present: (i) a chirality flip of the struck quark; (ii) a nonzero T-odd phase due to its final state interaction. So far…

High Energy Physics - Phenomenology · Physics 2011-02-01 Dmitry Ostrovsky , Edward Shuryak

I consider the question of the interaction between a QCD string and the spin of a quark or an antiquark on whose worldline the string terminates. The problem is analysed from the point of view of a string representation for the expectation…

High Energy Physics - Theory · Physics 2008-11-26 Vikram Vyas

Following Fr\"ohlich and Spencer, we study one dimensional Ising spin systems with ferromagnetic, long range interactions which decay as $|x-y|^{-2+\alpha}$, $0\leq \alpha\leq 1/2$. We introduce a geometric description of the spin…

Mathematical Physics · Physics 2011-11-09 M. Cassandro , P. A. Ferrari , I. Merola , E. Presutti

A generalization of the Lagrangian introduced earlier in [2011 {\it J. Phys. G} ${\bf 37}$ 105001] for a classical color spinning particle interacting with background non-Abelian gauge and fermion fields for purpose of considering a change…

High Energy Physics - Theory · Physics 2011-12-12 Yuri A. Markov , Margarita A. Markova , Alexey A. Shishmarev , Alexander N. Vall

The binding energy of the six quark system with strangeness s=-3 is investigated under the chiral SU(3) constituent quark model in the framework of $RGM$. The calculations of the single $N\Omega$ channel with spin S=2 and the single…

Nuclear Theory · Physics 2015-06-26 Q. B. Li , P. N. Shen