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Related papers: Polarization dynamics from moment equations

200 papers

We develop a quantum spin-density-matrix framework for heavy-quark spin dynamics in relativistic heavy-ion collisions. Starting from an initial polarization induced along the magnetic-field direction, we derive the evolution equation for…

High Energy Physics - Phenomenology · Physics 2026-05-08 Sunil Jaiswal , Sourav Dey , Amaresh Jaiswal

Many sets of polarization evolution equations have been suggested to describe the method of polarization buildup by spin filtering in storage rings. In this paper a generic system of polarization evolution equations describing spin…

High Energy Physics - Phenomenology · Physics 2008-11-26 D. S. O'Brien

We summarize the key ingredients of the recently proposed formalism of relativistic perfect-fluid hydrodynamics with spin. Based on the underlying kinetic theory definitions for the equilibrium distribution functions we obtain the evolution…

Nuclear Theory · Physics 2020-08-26 Radoslaw Ryblewski , Rajeev Singh

Semiclassical expansion of the Wigner function for spin-1/2 fermions having an effective spacetime-dependent mass is used to analyze spin-polarization effects. The existing framework is reformulated to obtain a differential equation…

High Energy Physics - Phenomenology · Physics 2024-01-24 Samapan Bhadury , Arpan Das , Wojciech Florkowski , Gowthama K. K. , Radoslaw Ryblewski

We study the inverse problem of deducing the dynamical characteristics (such as the potential field) of large systems from kinematic observations. We show that, for a class of steady-state systems, the solution is unique even with…

Astrophysics · Physics 2008-11-14 Mikko Kaasalainen

We consider the motion of a finite though large number of particles in the whole space R n. Particles move freely until they experience pairwise collisions. We use our recent theory of divergence-controlled positive symmetric tensors in…

Analysis of PDEs · Mathematics 2019-03-15 Denis Serre

With this paper we extend our studies [1] on polarized beams by distilling tools from the theory of principal bundles. Four major theorems are presented, one which ties invariant fields with the notion of normal form, one which allows one…

Accelerator Physics · Physics 2014-12-15 Klaus Heinemann , James A. Ellison , Desmond P. Barber , Mathias Vogt

By solving a simple kinetic equation, in the relaxation time approximation, and for a particular set of moments of the distribution function, we establish a set of equations which, on the one hand, capture exactly the dynamics of the…

Nuclear Theory · Physics 2018-03-07 Jean-Paul Blaizot , Li Yan

We review the theoretical framework for the calculation of particle polarization in relativistic heavy ion collisions within the hydrodynamical model. The covariant decomposition of the mean spin vector is presented and open theoretical…

Nuclear Theory · Physics 2018-03-14 F. Becattini

Dynamics of systems of structured particles consisting of potentially interacting material points is considered in the framework of classical mechanics. Equations of interaction and motion of structured particles have been derived. The…

General Physics · Physics 2012-05-14 V. M. Somsikov

We derive an expression for the tensor polarization of a system of massive spin-1 particles in a hydrodynamic framework. Starting from quantum kinetic theory based on the Wigner-function formalism, we employ a modified method of moments…

Nuclear Theory · Physics 2023-03-09 David Wagner , Nora Weickgenannt , Enrico Speranza

After a brief introduction into the general importance of polarization observables for the analysis of a reaction, the basic density matrix formalism for the description of polarization phenomena is outlined and illustrated by explicit…

Nuclear Theory · Physics 2015-05-13 Hartmuth Arenhoevel

As the core ingredient for spin polarization, the local equilibrium spin distribution function is derived from the detailed balance principle. The kinetic theory for interacting fermionic systems is applied to the Nambu--Jona-Lasinio model…

High Energy Physics - Theory · Physics 2021-09-29 Ziyue Wang , Xingyu Guo , Pengfei Zhuang

We demonstrate that the multipoles associated with the density matrix are truly observable quantities that can be unambiguously determined from intensity moments. Given their correct transformation properties, these multipoles are the…

The dynamics of a localized molecular spin under the influence of external voltage pulses is addressed using a generalized spin equation of motion. The approach incorporates anisotropic fields, non-equilibrium conditions, and non-adiabatic…

Mesoscale and Nanoscale Physics · Physics 2018-12-05 Henning Hammar , Jonas Fransson

We discuss the information that can be deduced from a measurement of particle (hyperon or vector meson) polarization in ultrarelativistic nuclear collisions. We describe the sensitivity of polarization to initial conditions, hydrodynamic…

Nuclear Theory · Physics 2008-11-26 Barbara Betz , Miklos Gyulassy , Giorgio Torrieri

We present an analytically solvable model based on the blast-wave picture of heavy-ion collisions with flow-momentum correspondence. It can describe the key features of spin polarizations in heavy-ion collisions. With the analytical…

Nuclear Theory · Physics 2024-11-27 Anum Arslan , Wen-Bo Dong , Guo-Liang Ma , Shi Pu , Qun Wang

Quantum mechanical equations of motion are obtained for particles and spin in media with polarized electrons in the presence of external fields. The motion of electrons and their spins is governed by the exchange interaction, while the…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. J. Silenko

Intermediate-energy heavy-ion collisions can produce a spin polarization of the projectile-like species. Spin polarization has been observed for both nucleon removal and nucleon pickup processes. Qualitative agreement with measured spin…

Nuclear Experiment · Physics 2008-11-26 D. E. Groh , J. S. Pinter , P. F. Mantica , T. J. Mertzimekis , A. E. Stuchbery , D. T. Khoa

General features of the formalism describing hydrodynamic evolution of transversally thermalized matter possibly produced at the very early stages of ultra-relativistic heavy-ion collisions are presented. Thermodynamical consistency of the…

Nuclear Theory · Physics 2009-10-02 Radoslaw Ryblewski