English
Related papers

Related papers: Spin alignment of vector mesons by glasma fields

200 papers

The spin alignment of vector meson produced in high energy reactions is determined by the spin-dependent fragmentation function $D_{1LL} (z,\mu_f)$ that is shown to be independent of the polarization of the fragmenting quark. In this paper,…

High Energy Physics - Phenomenology · Physics 2021-02-03 Kai-bao Chen , Zuo-tang Liang , Yu-kun Song , Shu-yi Wei

The significant global spin alignment observed for $\phi$ mesons in heavy-ion collisions has sparked intense discussions about its origin and implications. One explanation suggests that fluctuations in the strong force field may introduce…

Nuclear Theory · Physics 2024-08-01 Diyu Shen , Jinhui Chen , Aihong Tang

We argue that spin alignment of the vector mesons observed in unpolarized hadron-hadron collisions is closely related to the single spin left-right asymmetry observed in transversely polarized hadron-hadron collisions. We present the…

High Energy Physics - Phenomenology · Physics 2009-11-10 Qing-hua Xu , Zuo-tang Liang

We find evidence of the alignment of the azimuthal angle of the spin vectors of quasars in large quasar groups of different redshift. This effect is probably of cosmological origin and could be explained by symmetry breaking of the…

General Relativity and Quantum Cosmology · Physics 2020-12-23 Reinoud Jan Slagter

Different bases for the spin-1 density matrix are discussed to clarify the connection between its components and observables measured in heavy-ion collisions. The theoretical advantage of using the adjoint representation for spin matrices…

Nuclear Theory · Physics 2026-02-03 Wojciech Florkowski , Sudip Kumar Kar , Valeriya Mykhaylova

Unexpectedly large and puzzling spin alignment, and thus tensor polarization, of vector mesons has been observed in heavy-ion collisions. Given that tensor polarization represents a fluctuation of spin, we derive, for the first time, a…

Nuclear Theory · Physics 2025-11-18 Feng Li , Shuai Y. F. Liu

We calculate the spin density matrix of the vector meson produced in e+e- annihilation at Z^0 pole. We show that the data imply a significant polarization for the antiquark which is created in the fragmentation process of the polarized…

High Energy Physics - Phenomenology · Physics 2009-12-31 Qing-hua Xu , Chun-xiu Liu , Zuo-tang Liang

We develop a general framework for studying the spin alignment $\rho_{00}$ for flavorless vector mesons by using the gauge/gravity duality. Focusing on the dilepton production through vector meson decay, we derive the relation between…

High Energy Physics - Phenomenology · Physics 2024-03-13 Xin-Li Sheng , Yan-Qing Zhao , Si-Wen Li , Francesco Becattini , Defu Hou

We estimate both the polarization of spin $1/2$ baryons and the spin density matrix coefficients of spin $1$ mesons using a thermal model that incorporates vorticity and polarization to describe quarks, along with a coalescence formalism…

High Energy Physics - Phenomenology · Physics 2024-10-23 Kayman J. Gonçalves , Giorgio Torrieri , Radoslaw Ryblewski

As the spin alignment of a vector meson is predicted to be correlated with its spectral properties, we study the spectral properties of the $\phi$ meson using two microscopic Lagrangians based either on chiral effective field theory or the…

Nuclear Theory · Physics 2025-03-18 Zhong-Yuan Sun , You-Yu Li , Shuai Y. F. Liu

We consider the quantum kinetic-theory description for interacting massive spin-half fermions using the Wigner function formalism. We derive a general kinetic theory description assuming that the spin effects appear at the classical and…

High Energy Physics - Theory · Physics 2023-09-11 Arpan Das , Wojciech Florkowski , Avdhesh Kumar , Radoslaw Ryblewski , Rajeev Singh

We have derived the Wigner equations at global equilibrium with constant vorticity but space-time dependent electromagnetic fields up to second order in semiclassical expansion. We obtain the new second-order contributions to the charge…

High Energy Physics - Phenomenology · Physics 2024-09-24 Shi-Zheng Yang , Jian-Hua Gao , Shi Pu

The global spin alignment of vector mesons is a powerful probe to study the vorticity field of the system produced in non-central relativistic heavy-ion collisions. Since the experimental observables of global spin alignment are sensitive…

Nuclear Theory · Physics 2022-04-12 Chao Zhang , Peng Yang , Feng Liu , Biao Tu

Based on a generalized side-jump formalism for massless chiral fermions, which naturally takes into account the spin-orbit coupling in the scattering of two chiral fermions and the chiral vortical effect in a rotating chiral fermion matter,…

Nuclear Theory · Physics 2021-02-03 Shuai Y. F. Liu , Yifeng Sun , Che Ming Ko

Large scale correlations in the orientations of galaxies can result from alignments in their angular momentum vectors. These alignments arise from the tidal torques exerted on neighboring proto-galaxies by the smoothly varying shear field.…

Astrophysics · Physics 2009-07-09 Robert G. Crittenden , Priyamvada Natarajan , Ue-Li Pen , Tom Theuns

The spin alignment of $J/\psi$ with respect to event plane in relativistic heavy ion collisions exhibits a significant signal. We propose a possible mechanism for spin alignment through spin dependent dissociation of quarkonia in a vortical…

High Energy Physics - Phenomenology · Physics 2025-07-17 Yuhao Liang , Shu Lin

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 derive the quantum kinetic equations for massive and massless quarks coupled with the background chromo-electromagnetic fields from the Wigner-function approach with the $\hbar$ expansion and effective power-counting scheme. For each…

High Energy Physics - Phenomenology · Physics 2022-06-29 Di-Lun Yang

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 spin ordering of a quantum dot defined via magnetic barriers in an interacting quantum spin Hall edge. The spin-resolved density-density correlation functions are computed. We show that strong electron interactions induce a…

Mesoscale and Nanoscale Physics · Physics 2013-09-12 G. Dolcetto , N. Traverso Ziani , M. Biggio , F. Cavaliere , M. Sassetti